Nouns denoting substances
- 1-dodecanol
- a colorless insoluble solid alcohol used to make detergents and pharmaceuticals
- 18-karat gold
- an alloy that contains 75 per cent gold
- 2-hydroxybenzoic acid
- a white crystalline substance with a bitter aftertaste; used as a fungicide or in making aspirin or dyes or perfumes
- 2-methylpropenoic acid
- an unsaturated acid (C4H6O2) used to make resins and plastics
- 22-karat gold
- an alloy that contains 87 per cent gold
- 24-karat gold
- 100 per cent gold
- 5-hydroxy-3-methylglutaryl-coenzyme A reductase
- a liver enzyme that is responsible for producing cholesterol
- 5-hydroxytryptamine
- a neurotransmitter involved in e.g. sleep and depression and memory
- A
- (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
- A
- one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
- aa
- a dry form of lava resembling clinkers
- ABO antibodies
- blood type antibodies
- abradant
- a substance that abrades or wears down
- ABS
- any of a class of composite plastics used to make car bodies and cases for computers and other appliances
- absinthe oil
- a dark bitter oil obtained from wormwood leaves; flavors absinthe liqueurs
- absolute alcohol
- pure ethyl alcohol (containing no more than 1% water)
- absorbate
- a material that has been or is capable of being absorbed
- absorbent cotton
- cotton made absorbent by removal of the natural wax
- absorbent
- a material having capacity or tendency to absorb another substance
- absorber
- (physics) material in a nuclear reactor that absorbs radiation
- absorption indicator
- an indicator used in reactions that involve precipitation
- Ac
- a radioactive element of the actinide series; found in uranium ores
- acaracide
- a chemical agent used to kill mites
- acaroid resin
- an alcohol-soluble resin from Australian trees; used in varnishes and in manufacturing paper
- accelerator
- (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected
- acceptor
- (chemistry) in the formation of a coordinate bond it is the compound to which electrons are donated
- acceptor RNA
- RNA molecules present in the cell (in at least 20 varieties, each variety capable of combining with a specific amino acid) that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell (according to directions coded in the mRNA)
- ACE
- proteolytic enzyme that converts angiotensin I into angiotensin II
- acetal
- any organic compound formed by adding alcohol molecules to aldehyde molecules
- acetaldehyde
- a colorless volatile water-soluble liquid aldehyde used chiefly in the manufacture of acetic acid and perfumes and drugs
- acetaldol
- unsaturated aldol
- acetamide
- a colorless solid amide of acetic acid used as a solvent and in the synthesis of organic compounds
- acetate
- a salt or ester of acetic acid
- acetic acid
- a colorless pungent liquid widely used in manufacturing plastics and pharmaceuticals
- acetic anhydride
- a compound that is needed in order to refine opium into heroin
- acetin
- any of three liquid acetates that are formed when acetic acid and glycerin are heated together
- acetoacetic acid
- unstable acid found in abnormal amounts in the blood and urine in some cases of impaired metabolism (as diabetes mellitus or starvation)
- acetone body
- a ketone that is an intermediate product of the breakdown of fats in the body; any of three compounds (acetoacetic acid, acetone, and/or beta-hydroxybutyric acid) found in excess in blood and urine of persons with metabolic disorders
- acetone
- the simplest ketone; a highly flammable liquid widely used as an organic solvent and as material for making plastics
- acetum
- a dilute solution of acetic acid that is used as a solvent (e.g. for a drug)
- acetyl chloride
- colorless liquid acyl chloride (CH3COCl) that has a pungent odor
- acetyl
- the organic group of acetic acid (CH3CO-)
- acetylcholine
- a neurotransmitter that is a derivative of choline; released at the ends of nerve fibers in the somatic and parasympathetic nervous systems
- acetylene
- a colorless flammable gas used chiefly in welding and in organic synthesis
- acid
- any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
- acid anhydrides
- organic compounds that react with water to form an acid
- acid dye
- dye in which the chromophore is part of a negative ion
- acid halide
- organic compounds containing the group -COX where X is a halogen atom
- acid hydrogen
- a hydrogen atom in an acid that forms a positive ion when the acid dissociates
- acid-base indicator
- an indicator that changes color on going from acidic to basic solutions
- acrolein
- a pungent colorless unsaturated liquid aldehyde made from propene
- acrylamide
- a white crystalline amide of propenoic acid can damage the nervous system and is carcinogenic in laboratory animals
- acrylate resin
- a glassy thermoplastic; can be cast and molded or used in coatings and adhesives
- acrylate
- a salt or ester of propenoic acid
- acrylic acid
- an unsaturated liquid carboxylic acid used in the manufacture of acrylic resins
- acrylic
- polymerized from acrylonitrile
- acrylonitrile
- a colorless liquid unsaturated nitrile made from propene
- actin
- one of the proteins into which actomyosin can be split; can exist in either a globular or a fibrous form
- actinide series
- (chemistry) a series of 15 radioactive elements with increasing atomic numbers from actinium to lawrencium
- actinide
- any of a series of radioactive elements with atomic numbers 89 through 103
- actinolite
- a green mineral of the amphibole group; calcium magnesium iron silicate
- activated carbon
- powdered or granular carbon used for purifying by adsorption; given orally (as a slurry) it is an antidote for some kinds of poisons
- activating agent
- (mineral extraction) a surface-active chemical used in flotation process to increase the attraction to a specific mineral
- activator
- (biology) any agency bringing about activation; a molecule that increases the activity of an enzyme or a protein that increases the production of a gene product in DNA transcription
- active
- chemical agent capable of activity
- actomyosin
- a protein complex in muscle fibers; composed of myosin and actin; shortens when stimulated and causes muscle contractions
- acyl
- any group or radical of the form RCO- where R is an organic group
- acylglycerol
- an ester of glycerol and fatty acids that occurs naturally as fats and fatty oils
- ADA
- an enzyme found in mammals that can catalyze the deamination of adenosine into inosine and ammonia
- adamant
- very hard native crystalline carbon valued as a gem
- adduct
- a compound formed by an addition reaction
- adenosine
- (biochemistry) a nucleoside that is a structural component of nucleic acids; it is present in all living cells in a combined form as a constituent of DNA and RNA and ADP and ATP and AMP
- ader wax
- a waxy mineral that is a mixture of hydrocarbons and occurs in association with petroleum; some varieties are used in making ceresin and candles
- adesite
- dark greyish extrusive rock
- adhesive
- a substance that unites or bonds surfaces together
- adipic acid
- a carboxylic acid used in the manufacture of nylon
- Admiralty Metal
- alpha-beta brass containing tin; resistant to sea water; Admiralty Metal is a trademark
- adobe
- the clay from which adobe bricks are made
- ADP
- an ester of adenosine that is converted to ATP for energy storage
- adrenal cortical steroid
- a steroid hormone produced by the adrenal cortex or synthesized; administered as drugs they reduce swelling and decrease the body's immune response
- adrenosterone
- a steroid having androgenic activity; obtained from the cortex of the adrenal gland
- adsorbate
- a material that has been or is capable of being adsorbed
- adsorbent
- a material having capacity or tendency to adsorb another substance
- adulterant
- any substance that lessens the purity or effectiveness of a substance
- aflatoxin
- a potent carcinogen from the fungus Aspergillus; can be produced and stored for use as a bioweapon
- AFP
- an abnormally large amount of this fetoprotein in the fetus can signal an abnormality of the neural tube (as spina bifida or anencephaly)
- afterdamp
- a toxic mixture of gases (including carbon dioxide and carbon monoxide and nitrogen) after an explosion of firedamp in a mine
- Ag
- a soft white precious univalent metallic element having the highest electrical and thermal conductivity of any metal; occurs in argentite and in free form; used in coins and jewelry and tableware and photography
- agar
- a colloidal extract of algae; used especially in culture media and as a gelling agent in foods
- agar
- any culture medium that uses agar as the gelling agent
- agate
- an impure form of quartz consisting of banded chalcedony; used as a gemstone and for making mortars and pestles
- Agene
- a yellow pungent volatile oil (trade name Agene) formerly used for bleaching and aging flour
- agent
- a substance that exerts some force or effect
- Agent Orange
- a herbicide used in the Vietnam War to defoliate forest areas
- agglomerate
- volcanic rock consisting of large fragments fused together
- agglutinin
- an antibody that causes agglutination of a specific antigen
- agglutinogen
- any substance that acts as an antigen to cause agglutinin production
- aggregate
- material such as sand or gravel used with cement and water to make concrete, mortar, or plaster
- air
- a mixture of gases (especially oxygen) required for breathing; the stuff that the wind consists of
- air
- once thought to be one of four elements composing the universe (Empedocles)
- air cushion
- the trapped air that supports a hovercraft a short distance above the water or ground
- air gas
- a gas made of carbon monoxide and hydrogen and nitrogen; made by passing air over hot coke
- Al
- a silvery ductile metallic element found primarily in bauxite
- alabaster
- a compact fine-textured, usually white gypsum used for carving
- alanine
- a crystalline amino acid that occurs in many proteins
- Alar
- a chemical sprayed on fruit trees to regulate their growth so the entire crop can be harvested at one time
- albite
- a widely distributed feldspar that forms rocks
- albumen
- a simple water-soluble protein found in many animal tissues and liquids
- albuminoid
- a simple protein found in horny and cartilaginous tissues and in the lens of the eye
- alcahest
- hypothetical universal solvent once sought by alchemists
- alcapton
- an acid formed as an intermediate product of the metabolism of tyrosine and phenylalanine
- alcohol
- any of a series of volatile hydroxyl compounds that are made from hydrocarbons by distillation
- alcohol group
- the chemical group -OH
- Aldactone
- a synthetic corticosteroid (trade name Aldactone) used to treat hypertension
- aldehyde
- any of a class of highly reactive chemical compounds; used in making resins and dyes and organic acids
- aldehyde group
- the chemical group -CHO
- aldehyde-alcohol
- an oily colorless liquid obtained by the condensation of two molecules of acetaldehyde; contains an alcohol group (-OH) and an aldehyde group (-CHO)
- aldohexose
- a monosaccharide sugar having six carbon atoms and an aldehyde group
- aldose
- a monosaccharide sugar that contains the aldehyde group or is hemiacetal
- aldosterone
- a corticosteroid hormone that is secreted by the cortex of the adrenal gland; regulates salt (sodium and potassium) and water balance
- aleurone
- granular protein in outermost layer of endosperm of many seeds or cereal grains
- alexandrite
- a green variety of chrysoberyl used as a gemstone
- algin
- a gum used especially as a thickener or emulsifier
- alicyclic compound
- an aliphatic compound that contains a ring of atoms
- aliphatic compound
- organic compound that is an alkane or alkene or alkyne or their derivative
- alizarin carmine
- any of various acid dyes; used for dyeing wool scarlet red
- alizarin yellow
- any of various yellow dyes; not related chemically to alizarin but applied in the same manner
- alizarin
- an orange-red crystalline compound used in making red pigments and in dyeing
- Alka-seltzer
- a commercial antacid that contains aspirin; tablets dissolve in water to give an effervescent solution
- alkali
- a mixture of soluble salts found in arid soils and some bodies of water; detrimental to agriculture
- alkali metal
- any of the monovalent metals of group I of the periodic table (lithium or sodium or potassium or rubidium or cesium or francium)
- alkali
- any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water
- alkaline earth
- any of the bivalent metals of group II of the periodic table (calcium or strontium or barium or magnesium or beryllium)
- alkaliser
- an agent that counteracts or neutralizes acidity (especially in the stomach)
- alkaloid
- natural bases containing nitrogen found in plants
- alkane
- a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)
- alkene
- any unsaturated aliphatic hydrocarbon
- alkyd
- a durable synthetic resin widely used in adhesives and paints
- alkyl halide
- organic compound in which halogen atoms have been substituted for hydrogen atoms in an alkane
- alkyl
- any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons
- alkylbenzene
- organic compound that has an alkyl group bound to a benzene ring
- alkylbenzenesulfonate
- sulfonate of alkyl benzene
- allergen
- any substance that can cause an allergy
- alligator
- leather made from alligator's hide
- alloantibody
- an antibody that occurs naturally against foreign tissues from a person of the same species
- allomorph
- any of several different crystalline forms of the same chemical compound
- allotrope
- a structurally different form of an element
- alloy cast iron
- cast iron containing alloying elements (usually nickel or chromium or copper or molybdenum) to increase the strength or facilitate heat treatment
- alloy steel
- steel who characteristics are determined by the addition of other elements in addition to carbon
- alloy
- a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten
- alluvial soil
- a fine-grained fertile soil deposited by water flowing over flood plains or in river beds
- allyl alcohol
- an unsaturated primary alcohol present in wood spirit; use to make resins and plasticizers and pharmaceuticals
- allyl resin
- a resin derived from allyl alcohol that hardens when cured; used as an adhesive
- allyl
- the univalent unsaturated organic radical C3H5; derived from propylene
- almandine
- a purple variety of the ruby spinel
- almandine
- a deep red garnet consisting of iron aluminum silicate
- Alnico
- trade name for an alloy used to make high-energy permanent magnets; contains aluminum and iron and nickel plus cobalt or copper or titanium
- alpaca
- wool of the alpaca
- alpha brass
- an alloy of brass and zinc; used mainly for cold working
- alpha bronze
- an alloy of copper and tin that can be worked
- alpha globulin
- a globulin in blood plasma or serum that is alkaline and has great electrophoretic mobility
- alpha iron
- a magnetic allotrope of iron; stable below 906 degrees centigrade
- alpha-linolenic acid
- a polyunsaturated fatty acid with 18 carbon atoms; the only omega-3 fatty acid found in vegetable products; it is most abundant in canola oil; a fatty acid essential for nutrition
- alpha-naphthol
- an isomer of naphthol used in dyes
- alpha-tocopheral
- a potent form of vitamin E obtained from germ oils or by synthesis
- alum
- a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum
- alum
- a white crystalline double sulfate of aluminum: the potassium double sulfate of aluminum
- alumina
- any of various forms of aluminum oxide occurring naturally as corundum
- aluminate
- a compound of alumina and a metallic oxide
- aluminium bronze
- an alloy of copper and aluminum with high tensile strength and resistance to corrosion
- aluminium chloride
- a chloride used as a wood preservative or catalyst
- aluminium hydroxide
- white crystalline compound that occurs naturally as the mineral gibbsite
- alundum
- a substance made of fused alumina
- Am
- a radioactive transuranic metallic element; discovered by bombarding uranium with helium atoms
- amalgam
- an alloy of mercury with another metal (usually silver) used by dentists to fill cavities in teeth; except for iron and platinum all metals dissolve in mercury and chemists refer to the resulting mercury mixtures as amalgams
- amber
- a hard yellowish to brownish translucent fossil resin; used for jewelry
- ambergris
- waxy substance secreted by the sperm whale and found floating at sea or washed ashore; used in perfume
- amblygonite
- a white or grey mineral consisting of lithium aluminum phosphate; a source of lithium
- ambrosia
- a mixture of nectar and pollen prepared by worker bees and fed to larvae
- amethyst
- a transparent purple variety of quartz; used as a gemstone
- amide
- any organic compound containing the group -CONH2
- amine
- a compound derived from ammonia by replacing hydrogen atoms by univalent hydrocarbon radicals
- amino acid
- organic compounds containing an amino group and a carboxylic acid group
- amino plastic
- a plastic (synthetic resin) made from amino compounds; used as an adhesive and as a coating for paper and textiles
- amino
- the radical -NH2
- aminobenzine
- oily poisonous liquid amine obtained from nitrobenzene and used to make dyes and plastics and medicines
- aminobenzoic acid
- a derivative of benzoic acid
- aminomethane
- a methyl with the hydrogen atom replaced by an amino radical
- aminopherase
- a class of transferases that catalyze transamination (that transfer an amino group from an amino acid to another compound)
- ammine
- a complex inorganic compound that contains ammonia molecules
- ammonia
- a pungent gas compounded of nitrogen and hydrogen (NH3)
- ammonia
- a water solution of ammonia
- ammoniac
- the aromatic gum of the ammoniac plant
- ammonium carbamate
- a salt of carbamic acid that is used as a nitrogen fertilizer
- ammonium carbonate
- a carbonate of ammonium; used in the manufacture of smelling salts and baking powder and ammonium compounds
- ammonium chloride
- a white salt used in dry cells
- ammonium nitrate
- used as an explosive and fertilizer and rocket propellant
- ammonium
- the ion NH4 derived from ammonia; behaves in many respects like an alkali metal ion
- ammunition
- any nuclear or chemical or biological material that can be used as a weapon of mass destruction
- AMP
- a nucleotide found in muscle cells and important in metabolism; reversibly convertible to ADP and ATP
- amphibole
- a mineral or mineral variety belonging to the amphibole group
- amphibole group
- a group of minerals with similar crystal structures containing a silicate chain and combinations of chiefly sodium and calcium and magnesium and iron and aluminum
- amphibolite
- a metamorphic rock composed chiefly of amphibole and plagioclase
- amygdalin
- a bitter cyanogenic glucoside extracted from the seeds of apricots and plums and bitter almonds
- amygdaloid
- volcanic rock in which rounded cavities formed by expanding gas have subsequently become filled with mineral deposits
- amyl
- a hydrocarbon radical that occurs in many organic compounds
- amyl alcohol
- a mixture of 2 or more isomeric alcohols; used as a solvent and in organic synthesis
- amylase
- any of a group of proteins found in saliva and pancreatic juice and parts of plants; help convert starch to sugar
- amyloid
- (pathology) a waxy translucent complex protein resembling starch that results from degeneration of tissue
- amyloid
- a non-nitrogenous food substance consisting chiefly of starch; any substance resembling starch
- amylum
- a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice; an important foodstuff and used otherwise especially in adhesives and as fillers and stiffeners for paper and textiles
- anabolic steroid
- any of a group of synthetic steroid hormones used to stimulate muscle and bone growth; more than 100 have been developed and each requires a prescription to be used legally in the United States; sometimes used illicitly by athletes to increase their strength
- anatoxin
- a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin
- andesite
- a dark grey volcanic rock
- andradite
- a garnet consisting of calcium iron silicate and having any color ranging from yellow and green to brown and black; used as gemstone
- androgen
- male sex hormone that is produced in the testes and responsible for typical male sexual characteristics
- androsterone
- an androgenic hormone that is less active than testosterone
- anhydride
- a compound formed from one or more other compounds in a reaction resulting in removal of water
- anil
- a blue dye obtained from plants or made synthetically
- aniline dye
- any of many dyes made from aniline
- animal black
- black substance containing char in the form of carbonized bone; used as a black pigment
- animal fat
- any fat obtained from animals
- animal fiber
- fiber derived from animals
- animal glue
- a protein gelatin obtained by boiling e.g. skins and hoofs of cattle and horses
- animal material
- material derived from animals
- animal oil
- any oil obtained from animal substances
- animal pigment
- pigment occurring in animals
- animal product
- a product made from animal material
- animal skin
- the outer covering of an animal
- animal starch
- one form in which body fuel is stored; stored primarily in the liver and broken down into glucose when needed by the body
- animal toxin
- a toxin resembling bacterial toxins in its antigenic properties that is found in the fluids of certain animals
- anime
- any of various resins or oleoresins
- anionic compound
- a compound characterized by an active anion
- anionic
- a class of synthetic detergents in which the molecules do not ionize in aqueous solutions
- anorthite
- rare plagioclastic feldspar occurring in many igneous rocks
- anthophyllite
- a dark brown mineral of the amphibole group; magnesium iron silicate
- anthracite
- a hard natural coal that burns slowly and gives intense heat
- antibody
- any of a large variety of proteins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response
- anticatalyst
- (chemistry) a substance that retards a chemical reaction or diminishes the activity of a catalyst
- antifreeze
- a liquid added to the water in a cooling system to lower its freezing point
- antigen
- any substance (as a toxin or enzyme) that stimulates an immune response in the body (especially the production of antibodies)
- antigenic determinant
- the site on the surface of an antigen molecule to which an antibody attaches itself
- antiknock
- any of various compounds that are added to gasoline to reduce engine knocking
- antimatter
- matter consisting of elementary particles that are the antiparticles of those making up normal substances
- antimonial lead
- a lead alloy that contains about 5% antimony
- antimony potassium tartrate
- a poisonous colorless salt used as a mordant and in medicine
- antioxidant
- substance that inhibits oxidation or inhibits reactions promoted by oxygen or peroxides
- antitoxin
- an antibody that can neutralize a specific toxin
- antivenene
- an antitoxin that counteracts the effects of venom from the bite of a snake or insect or other animal
- apatite
- a common complex mineral consisting of calcium fluoride phosphate or calcium chloride phosphate; a source of phosphorus
- aphanite
- fine-grained homogeneous rock (such as basalt) containing minerals undetectable by the naked eye
- aplite
- light-colored and fine-grained granitic rock consisting chiefly of quartz and feldspars
- apoenzyme
- a protein that combines with a coenzyme to form an active enzyme
- aqua fortis
- acid used especially in the production of fertilizers and explosives and rocket fuels
- aqua regia
- a yellow fuming corrosive mixture of nitric and hydrochloric acid that dissolves metals (including gold)
- aquamarine
- a transparent variety of beryl that is blue green in color
- aqueous solution
- a solution in water
- Ar
- a colorless and odorless inert gas; one of the six inert gases; comprises approximately 1% of the earth's atmosphere
- aragonite
- a mineral form of crystalline calcium carbonate; dimorphic with calcite
- archil
- a purplish dye obtained from orchil lichens
- arenaceous rock
- a sedimentary rock composed of sand
- argent
- a metal tincture used in heraldry to give a silvery appearance
- argentite
- a valuable silver ore consisting of silver sulfide (Ag2S)
- argil
- a white clay (especially a white clay used by potters)
- argillaceous rock
- a sedimentary rock formed from clay deposits
- argillite
- a sedimentary rock differing from shale in being bound by silica and from slate in having no slate cleavages
- arginine
- a bitter tasting amino acid found in proteins and necessary for nutrition; its absence from the diet leads to a reduced production of spermatozoa
- argonon
- any of the chemically inert gaseous elements of the helium group in the periodic table
- argyrodite
- a rare steel-grey mineral consisting of silver and germanium and sulfur
- Aristocort
- a synthetic corticosteroid (trade names Aristocort or Aristopak or Kenalog) used as an anti-inflammatory agent
- aromatic compound
- a hydrocarbon containing one or more benzene rings that are characteristic of the benzene series of compounds
- aromatic hydrocarbon
- a hydrocarbon that contains one or more benzene rings that are characteristic of the benzene series of organic compounds
- arrowroot
- a nutritive starch obtained from the root of the arrowroot plant
- arsenate
- a salt or ester of arsenic acid
- arsenic acid
- an acid formed from arsenic pentoxide
- arsenic group
- the univalent group derived from arsine
- arsenic
- a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer
- arsenical
- a pesticide or drug containing arsenic
- arsenide
- a compound of arsenic with a more positive element
- arsenopyrite
- a silver-white or grey ore of arsenic
- arsine
- a poisonous colorless flammable gas used in organic synthesis and to dope transistors and as a poison gas in warfare
- art paper
- a high-quality paper (usually having a filler of china clay)
- artificial blood
- a liquid that can carry large amounts of oxygen and can serve as a temporary substitute for blood
- As
- a very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgar
- asa dulcis
- gum resin used especially in treating skin irritation
- asafetida
- the brownish gum resin of various plants; has strong taste and odor; formerly used as an antispasmodic
- asbestos
- a fibrous amphibole; used for making fireproof articles; inhaling fibers can cause asbestosis or lung cancer
- ash
- the residue that remains when something is burned
- asparagine
- a crystalline amino acid found in proteins and in many plants (e.g., asparagus)
- aspartic acid
- a crystalline amino acid found in proteins and occurring naturally in sugar beets and sugar cane
- asphalt
- mixed asphalt and crushed gravel or sand; used especially for paving but also for roofing
- asphalt
- a dark bituminous substance found in natural beds and as residue from petroleum distillation; consists mainly of hydrocarbons
- assay
- a substance that is undergoing an analysis of its components
- astrakhan
- the fur of young lambs
- At
- a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium
- atar
- essential oil or perfume obtained from flowers
- atom
- (physics and chemistry) the smallest component of an element having the chemical properties of the element
- atom
- (nontechnical usage) a tiny piece of anything
- ATP
- a nucleotide derived from adenosine that occurs in muscle tissue; the major source of energy for cellular reactions
- atrazine
- a synthetic compound derived from triazine that is widely used as an agricultural herbicide
- attar of roses
- a volatile fragrant oil obtained from fresh roses by steam distillation
- Au
- a soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia
- augite
- dark-green to black glassy mineral of the pyroxene group containing large amounts of aluminum and iron and magnesium
- austenite
- a solid solution of ferric carbide or carbon in iron; cools to form pearlite or martensite
- austenitic manganese steel
- a steel with a relatively large component (10-14%) of manganese; highly resistant to wear and shock
- austenitic steel
- steel that has enough nickel and chromium or manganese to retain austenite at atmospheric temperatures
- autoantibody
- an antibody acting against tissues of the organism that produces it
- auxin
- a plant hormone that promotes root formation and bud growth
- aventurine
- a translucent quartz spangled with bits of mica or other minerals
- axle grease
- a thick heavy grease used to lubricate axles
- azadirachtin
- insecticide
- azide
- a chemical compound containing the azido group combined with an element or radical
- azido group
- the univalent group N3- derived from hydrazoic acid
- azo dye
- any dye containing one or more azo groups
- azo group
- the bivalent group -N=N- united to two hydrocarbon groups
- azote
- an obsolete name for nitrogen
- azurite
- blue carbonate of copper; blue malachite
- B
- a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder
- B-complex vitamin
- originally thought to be a single vitamin but now separated into several B vitamins
- Ba
- a soft silvery metallic element of the alkali earth group; found in barite
- Babbitt metal
- an alloy of tin with some copper and antimony; a lining for bearings that reduces friction
- backlog
- the large log at the back of a hearth fire
- bacteriacide
- any chemical agent that destroys bacteria
- bacterial toxin
- any endotoxin or exotoxin formed in or elaborated by bacterial cells
- bacteriostat
- a chemical or biological material that inhibits bacterial growth
- baddeleyite
- a mineral consisting of zirconium oxide
- bagasse
- the dry dusty pulp that remains after juice is extracted from sugar cane or similar plants
- Bakelite
- a thermosetting plastic used as electric insulators and for making plastic ware and telephone receivers etc.
- baking powder
- any of various powdered mixtures used in baking as a substitute for yeast
- baking soda
- a white soluble compound (NaHCO3) used in effervescent drinks and in baking powders and as an antacid
- balas
- a pale rose-colored variety of the ruby spinel
- baleen
- a horny material from the upper jaws of certain whales; used as the ribs of fans or as stays in corsets
- ballast
- coarse gravel laid to form a bed for streets and railroads
- Ballistite
- an explosive (trade name Ballistite) that burns with relatively little smoke; contains pyrocellulose and is used as a propellant
- balm
- any of various aromatic resinous substances used for healing and soothing
- balm of Gilead
- a fragrant oleoresin
- balsam
- any of various fragrant oleoresins used in medicines and perfumes
- balsam capivi
- an oleoresin used in varnishes and ointments
- banana oil
- a liquid ester derived from amyl alcohol; has the odor of bananas
- bank gravel
- gravel as found in natural deposits
- barbituric acid
- a white crystalline acid derived from pyrimidine; used in preparing barbiturate drugs
- barf
- the matter ejected in vomiting
- barite
- a white or colorless mineral (BaSO4); the main source of barium
- barium dioxide
- a white toxic powder obtained by heating barium oxide in air
- barium hydroxide
- white poisonous crystals; made by dissolving barium oxide in water
- barium monoxide
- an oxide of barium; a whitish toxic powder
- barium sulfate
- a white insoluble radiopaque powder used as a pigment
- barm
- a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey
- baryta
- any of several compounds of barium
- basalt
- the commonest type of solidified lava; a dense dark grey fine-grained igneous rock that is composed chiefly of plagioclase feldspar and pyroxene
- base metal
- a metal that is common and not considered precious
- base pair
- one of the pairs of chemical bases joined by hydrogen bonds that connect the complementary strands of a DNA molecule or of an RNA molecule that has two strands; the base pairs are adenine with thymine and guanine with cytosine in DNA and adenine with uracil and guanine with cytosine in RNA
- base
- a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)
- basic color
- a dye that is considered to be a base because the chromophore is part of a positive ion
- basic iron
- pig iron containing a high percentage of phosphorus; used in making steel by a process that removes the phosphorus
- basic slag
- slag produced in making steel; low in silica but having large amounts of calcium phosphate; useful as fertilizer
- bastnaesite
- a yellow-to-brown mineral that is a source of rare earth elements
- bath water
- water used for a bath
- batholite
- large mass of intrusive igneous rock believed to have solidified deep within the earth
- bathroom tissue
- a soft thin absorbent paper for use in toilets
- battery acid
- dilute sulfuric acid used in storage batteries
- bauxite
- a clay-like mineral; the chief ore of aluminum; composed of aluminum oxides and aluminum hydroxides; used as an abrasive and catalyst
- bdellium
- aromatic gum resin; similar to myrrh
- Be
- a light strong brittle grey toxic bivalent metallic element
- bearing brass
- a brass bushing or a lining for a bearing
- bearing metal
- an alloy (often of lead or tin base) used for bearings
- bearskin
- the pelt of a bear (sometimes used as a rug)
- beaver
- the soft brown fur of the beaver
- beef tallow
- tallow obtained from a bovine animal
- beeswax
- a yellow to brown wax secreted by honeybees to build honeycombs
- beet sugar
- sugar made from sugar beets
- bell metal
- bronze with 3 or 4 parts copper to 1 part tin; used in making bells
- Bengal kino
- dried juice of the dhak tree; used as an astringent
- bentonite
- an absorbent aluminum silicate clay formed from volcanic ash
- benzene
- a colorless liquid hydrocarbon; highly flammable; carcinogenic; the simplest of the aromatic compounds
- benzoate
- any salt or ester of benzoic acid
- benzoate of soda
- a white crystalline salt used as a food preservative and antiseptic
- benzofuran
- a colorless oily compound extracted from coal tar and used in manufacturing synthetic resins
- benzoic acid
- a white crystalline solid occurring in many resins
- benzoquinone
- any of a class of aromatic yellow compounds including several that are biologically important as coenzymes or acceptors or vitamins; used in making dyes
- benzoyl group
- the univalent radical derived from benzoic acid
- benzoyl peroxide
- a white crystalline peroxide used in bleaching (flour or oils or fats) and as a catalyst for free radical reactions
- benzyl
- the univalent radical derived from toluene
- beryl
- the chief source of beryllium; colored transparent varieties are valued as gems
- beryllium bronze
- a copper-base alloy containing beryllium
- beta endorphin
- an endorphin produced by the pituitary gland that suppresses pain
- beta globulin
- a globulin in blood plasma that carries iron
- beta iron
- an allotrope of iron that is the same as alpha iron except that it is nonmagnetic; stable between 768 and 906 degrees centigrade
- beta-carotene
- an isomer of carotene that is found in dark green and dark yellow fruits and vegetables
- beta-hydroxybutyric acid
- beta derivative of hydroxybutyric acid that is found in the blood and urine in some cases of impaired metabolism
- beta-lactamase
- enzyme produced by certain bacteria that inactivates penicillin and results in resistance to that antibiotic
- beta-naphthol
- an isomer of naphthol used in rubber as an antioxidant
- betaine
- a sweet tasting alkaloid that occurs in sugar beets
- Bh
- a transuranic element
- Bi
- a heavy brittle diamagnetic trivalent metallic element (resembles arsenic and antimony chemically); usually recovered as a by-product from ores of other metals
- bicarbonate
- a salt of carbonic acid (containing the anion HCO3) in which one hydrogen atom has been replaced; an acid carbonate
- bichloride of mercury
- a white poisonous soluble crystalline sublimate of mercury; used as a pesticide or antiseptic or wood preservative
- bichloride
- a compound containing two chlorine atoms per molecule
- bichromate
- a salt of the hypothetical dichromic acid
- bile acid
- any of the steroid acids generated in the liver and stored with bile
- bile salt
- a salt of bile acid and a base; functions as an emulsifier of lipids and fatty acids
- bilge
- water accumulated in the bilge of a ship
- bilirubin
- an orange-yellow pigment in the bile that forms as a product of hemoglobin; excess amounts in the blood produce the yellow appearance observed in jaundice
- bimetal
- material made by bonding together sheets of two different metals
- binary compound
- chemical compound composed of only two elements
- binder
- something used to bind separate particles together or facilitate adhesion to a surface
- binder board
- a cardboard used by bookbinders to make covers for books
- biocatalyst
- a biochemical catalyst such as an enzyme
- biomass
- plant materials and animal waste used as fuel
- biotite
- dark brown to black mica found in igneous and metamorphic rock
- birch oil
- a liquid ester with a strong odor of wintergreen; applied externally for minor muscle and joint pain
- birdlime
- a sticky adhesive that is smeared on small branches to capture small birds
- bister
- a water-soluble brownish-yellow pigment made by boiling wood soot
- bitartrate
- an acid tartrate; a hydrogen tartrate
- bitter principle
- any one of several hundred compounds having a bitter taste; not admitting of chemical classification
- bitter spar
- a light colored mineral consisting of calcium magnesium carbonate; a source of magnesium; used as a ceramic and as fertilizer
- bitumen
- any of various naturally occurring impure mixtures of hydrocarbons
- bituminous coal
- rich in tarry hydrocarbons; burns readily with a smoky yellow flame
- Bk
- a radioactive transuranic element; discovered by bombarding americium with helium
- black diamond
- an inferior dark diamond used in industry for drilling and polishing
- black ice
- a thin coating of ice (as from freezing mist) on a road or sidewalk; nearly invisible but very hazardous
- black lead
- used as a lubricant and as a moderator in nuclear reactors
- black opal
- a dark colored opal with internal reflections of green or red
- blackdamp
- the atmosphere in a mine following an explosion; high in carbon dioxide and incapable of supporting life
- blacking
- a substance used to produce a shiny protective surface on footwear
- blacktop
- a black bituminous material used for paving roads or other areas; usually spread over crushed rock
- blanching agent
- an agent that makes things white or colorless
- bleach liquor
- a solution containing bleaching agents that is used to bleach textiles or paper pulp
- bleaching clay
- an adsorbent clay that will remove coloring from oils
- bleaching powder
- a white powder comprised of calcium hydroxide and chloride and hypochlorite and used to bleach and/or disinfect
- blende
- an ore that is the chief source of zinc; consists largely of zinc sulfide in crystalline form
- blister copper
- an impure form of copper having a black blistered surface
- blistering agent
- a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote
- blood agar
- a culture medium containing whole blood as the nutrient
- blood glucose
- glucose in the bloodstream
- blood platelet
- tiny bits of protoplasm found in vertebrate blood; essential for blood clotting
- bloodstone
- green chalcedony with red spots that resemble blood
- blotter
- absorbent paper used to dry ink
- blow gas
- the gas leaving a generator during a blow period
- blubber
- an insulating layer of fat under the skin of whales and other large marine mammals; used as a source of oil
- blue copperas
- hydrated blue crystalline form of copper sulfate
- blue
- used to whiten laundry or hair or give it a bluish tinge
- blueprint paper
- sensitized paper used to make blueprints
- bluestone
- bluish-grey sandstone used for paving and building
- BM
- solid excretory product evacuated from the bowels
- board
- a stout length of sawn timber; made in a wide variety of sizes and used for many purposes
- body waste
- waste matter (as urine or sweat but especially feces) discharged from the body
- bog soil
- poorly drained soils on top of peat and under marsh or swamp vegetation
- bole
- a soft oily clay used as a pigment (especially a reddish brown pigment)
- bond
- a superior quality of strong durable white writing paper; originally made for printing documents
- bone ash
- ash left when bones burn; high in calcium phosphate; used as fertilizer and in bone china
- bone fat
- fatty matter in bones extracted with solvents or by boiling or steaming; used chiefly in candles and cheap soaps and in lubricating greases
- bone oil
- the liquid portion of bone fat; used as a lubricant and in leather manufacture
- bone
- the porous calcified substance from which bones are made
- bonemeal
- fertilizer made of ground bones
- boracic acid
- any of various acids containing boron and oxygen
- borate
- a salt or ester of boric acid
- borax
- an ore of boron consisting of hydrated sodium borate; used as a flux or cleansing agent
- boric acid
- a white or colorless slightly acid solid that is soluble in water and ethanol; used in the manufacture of glass and paper and adhesives and in detergents and as a flux in welding; also used as an antiseptic and food preservative
- bornite
- a mineral consisting of sulfides of copper and iron that is found in copper deposits
- boron trifluoride
- a pungent colorless gas
- borosilicate
- a salt of boric and silicic acids
- bottled gas
- hydrocarbon gases, usually propane or butane, kept under pressure
- bottom fermenting yeast
- brewer's yeast used in bottom fermentation of lager
- botulin
- potent bacterial toxin produced by the bacterium Clostridium botulinum that causes botulism; can be used as a bioweapon
- botulinum toxin
- any of several neurotoxins that are produced by the anaerobic bacterium Clostridium botulinum; causes muscle paralysis
- botulinum toxin A
- a neurotoxin (trade name Botox) that is used clinically in small quantities to treat strabismus and facial spasms and other neurological disorders characterized by abnormal muscle contractions; is also used by cosmetic surgeons to smooth frown lines temporarily
- boulder clay
- unstratified soil deposited by a glacier; consists of sand and clay and gravel and boulders mixed together
- bouncing putty
- a soft elastic silicone polymer that increases in elasticity with the application of force; used in the center of golf balls and as shock-absorbent padding
- bowstring hemp
- hemp obtained from the sansevieria
- box calf
- black calfskin leather tanned with chromium salts
- Br
- a nonmetallic heavy volatile corrosive dark brown liquid element belonging to the halogens; found in sea water
- brain sugar
- a simple sugar found in lactose
- bran
- broken husks of the seeds of cereal grains that are separated from the flour by sifting
- brand
- a piece of wood that has been burned or is burning
- brass
- an alloy of copper and zinc
- breath
- the air that is inhaled and exhaled in respiration
- breccia
- a rudaceous rock consisting of sharp fragments embedded in clay or sand
- brewer's yeast
- yeast used in fermenting beer
- bricks and mortar
- building material consisting of bricks laid with mortar between them
- brimstone
- an old name for sulfur
- brine
- water containing salts
- Brioschi
- an antacid
- Britannia metal
- an alloy similar to pewter
- broadtail
- the fur of a very young karakul lamb
- Brocadopa
- the levorotatory form of dopa (trade names Bendopa and Brocadopa and Larodopa); as a drug it is used to treat Parkinson's disease
- bromeosin
- a red fluorescent dye resulting from the action of bromine on fluorescein; used in cosmetics and as a biological stain for studying cell structures
- bromic acid
- an unstable acid used as an oxidizing agent
- bromide
- any of the salts of hydrobromic acid; formerly used as a sedative but now generally replaced by safer drugs
- Bromo-seltzer
- an antacid
- bromoform
- colorless liquid haloform CHBr3
- bromophenol blue
- a dye used as an acid-base indicator
- bromothymol blue
- a dye used as an acid-base indicator
- bronze
- an alloy of copper and tin and sometimes other elements; also any copper-base alloy containing other elements in place of tin
- brown coal
- intermediate between peat and bituminous coal
- brownstone
- a reddish brown sandstone; used in buildings
- brucine
- a bitter alkaloid poison resembling strychnine and extracted from nux vomica
- brushwood
- the wood from bushes or small branches
- buckminsterfullerene
- a spheroidal fullerene; the first known example of a fullerene
- buckskin
- a soft yellowish suede leather originally from deerskin but now usually from sheepskin
- buff
- a soft thick undyed leather from the skins of e.g. buffalo or oxen
- buffer
- (chemistry) an ionic compound that resists changes in its pH
- buffer solution
- a solution containing a buffer
- builder
- a substance added to soaps or detergents to increase their cleansing action
- building material
- material used for constructing buildings
- buna
- made by polymerizing butadiene
- buntal
- fine white Philippine fiber from stalks of unopened leaves of talipot palms; used in making hats
- burnt lime
- a white crystalline oxide used in the production of calcium hydroxide
- burnt sienna
- a reddish-brown pigment produced by roasting sienna
- burnt umber
- dark brown pigment obtained by heating umber
- butadiene
- a gaseous hydrocarbon C4H6; used in making synthetic rubbers
- butane
- occurs in natural gas; used in the manufacture of rubber and fuels
- butanoic acid
- an unpleasant smelling fatty acid found especially in butter
- butanol
- a flammable alcohol derived from butanes and used for solvents
- butanone
- colorless soluble flammable liquid ketone used as a solvent for resins and as a paint remover and in lacquers and cements and adhesives and cleaning fluids and celluloid
- butcher paper
- a strong wrapping paper that resists penetration by blood or meat fluids
- butene
- any of three isomeric hydrocarbons C4H8; all used in making synthetic rubbers
- butterfat
- the fatty substance of milk from which butter is made
- butyl
- a hydrocarbon radical (C4H9)
- butyl rubber
- synthetic rubber made by polymerizing isobutylene
- butyrin
- any of three glycerides of butyric acid
- C
- an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
- C
- one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
- C
- a base found in DNA and RNA and derived from pyrimidine; pairs with guanine
- C-reactive protein
- a byproduct of inflammation; a globulin that is found in the blood in some cases of acute inflammation
- C2H6
- a colorless odorless alkane gas used as fuel
- Ca
- a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals
- cabinet wood
- moderately dense wood used for cabinetwork
- cabochon
- a highly polished gem that is cut convexly but without facets
- cacodyl
- a poisonous oily liquid with a garlicky odor composed of 2 cacodyl groups; undergoes spontaneous combustion in dry air
- cadaverine
- a colorless toxic ptomaine with an unpleasant odor formed during the putrefaction of animal tissue
- cadmium orange
- orange-hued cadmium yellow pigment
- cadmium sulfide
- a yellow sulfide used chiefly as a pigment
- cadmium sulphide
- ore of cadmium; a rare yellowish mineral consisting of cadmium sulphide in crystalline form
- cadmium yellow
- pigment of cadmium sulfide and barium sulfate varying in hue from lemon yellow to orange
- cadmium yellow pale
- pale-hued cadmium yellow pigment
- caffein
- a bitter alkaloid found in coffee and tea that is responsible for their stimulating effects
- cairngorm
- a smoky yellow or brown quartz
- calamine
- a white mineral; a common ore of zinc
- calc-tufa
- a soft porous rock consisting of calcium carbonate deposited from springs rich in lime
- calcedony
- a milky or greyish translucent to transparent quartz
- calcite
- a common mineral consisting of crystallized calcium carbonate; a major constituent of limestone
- calcium bicarbonate
- a bicarbonate that is a major cause of hard water
- calcium carbide
- a grey salt of calcium (CaC) used in making acetylene
- calcium carbonate
- a salt found in nature as chalk or calcite or aragonite or limestone
- calcium chloride
- a deliquescent salt; used in de-icing and as a drying agent
- calcium hydrate
- a caustic substance produced by heating limestone
- calcium hydride
- a saltlike binary compound (CaH2) used as a reducing agent and source of hydrogen
- calcium hypochlorite
- any hypochlorite of calcium; used as a bleaching agent
- calcium lactate
- a white crystalline salt made by the action of lactic acid on calcium carbonate; used in foods (as a baking powder) and given medically as a source of calcium
- calcium nitrate
- a deliquescent salt that is soluble in water; sometimes used as a source of nitrogen in fertilizers
- calcium octadecanoate
- an insoluble calcium salt of stearic acid and palmitic acid; it is formed when soap is mixed with water that contains calcium ions and is the scum produced in regions of hard water
- calcium phosphate
- a phosphate of calcium; a main constituent of animal bones
- calcium sulfate
- a white salt (CaSO4)
- calcium-cyanamide
- a compound used as a fertilizer and as a source of nitrogen compounds
- calf
- fine leather from the skin of a calf
- caliche
- nitrate-bearing rock or gravel of the sodium nitrate deposits of Chile and Peru
- caliche
- crust or layer of hard subsoil encrusted with calcium-carbonate occurring in arid or semiarid regions
- calomel
- a tasteless colorless powder used medicinally as a cathartic
- camphor
- a resin obtained from the camphor tree; used in making celluloid and liniment
- camphor oil
- oil distilled from camphor resin
- Canada balsam
- yellow transparent exudate of the balsam fir; used as a transparent cement in optical devices (especially in microscopy) and as a mounting medium
- canavanine
- an amino acid found in the jack bean
- candelilla wax
- a hard brown wax that occurs as a coating on candelilla shrubs
- cane sugar
- sucrose obtained from sugar cane
- cannabin
- a resin obtained from the hemp plant; thought to be the active narcotic agent in marijuana
- cannel coal
- a bituminous coal that burns with a luminous flame
- capric acid
- a fatty acid found in animal oils and fats; has an unpleasant smell resembling goats
- caproic acid
- a fatty acid found in animal oils and fats or made synthetically; smells like goats
- caprylic acid
- a fatty acid having a rancid taste; found in butter and other fats and oils
- capsaicin
- colorless pungent crystalline compound derived from capsicum; source of the hotness of hot peppers of the genus Capsicum such as chili and cayenne and jalapeno
- carbamate
- a salt (or ester) of carbamic acid
- carbamic acid
- an acid that is known only by virtue of its salts (as ammonium carbamate) or its esters (as urethane)
- carbamide
- the chief solid component of mammalian urine; synthesized from ammonia and carbon dioxide and used as fertilizer and in animal feed and in plastics
- carbide
- a binary compound of carbon with a more electropositive element
- carbohydrate
- an essential structural component of living cells and source of energy for animals; includes simple sugars with small molecules as well as macromolecular substances; are classified according to the number of monosaccharide groups they contain
- carbolic acid
- a toxic white soluble crystalline acidic derivative of benzene; used in manufacturing and as a disinfectant and antiseptic; poisonous if taken internally
- Carboloy
- an alloy based on tungsten with cobalt or nickel as a binder; used in making metal-cutting tools
- carbon 14
- a radioactive isotope of carbon
- carbon atom
- an atom of carbon
- carbon black
- a black colloidal substance consisting wholly or principally of amorphous carbon and used to make pigments and ink
- carbon disulfide
- a toxic colorless flammable liquid (CS2); used in the manufacture of rayon and cellophane and carbon tetrachloride and as a solvent for rubber
- carbon nanotube
- a fullerene molecule having a cylindrical or toroidal shape
- carbon steel
- steel whose characteristics are determined by the amount of carbon it contains
- carbon tet
- a colorless nonflammable liquid used as a solvent for fats and oils; because of its toxicity its use as a cleaning fluid or fire extinguisher has declined
- carbon tetrahalide
- compounds composed of 1 carbon and 4 halogen molecules
- carbon
- a thin paper coated on one side with a dark waxy substance (often containing carbon); used to transfer characters from the original to an under sheet of paper
- carbonate
- a salt or ester of carbonic acid (containing the anion CO3)
- carbonic acid
- a weak acid known only in solution; formed when carbon dioxide combines with water
- carbonyl
- a compound containing metal combined with carbon monoxide
- carbonyl group
- the bivalent radical CO
- carborundum
- an abrasive composed of silicon carbide crystals
- carboxyl
- the univalent radical -COOH; present in and characteristic of organic acids
- carboxylic acid
- an organic acid characterized by one or more carboxyl groups
- carboxymethyl cellulose
- an acid derivative of cellulose
- carbuncle
- deep-red cabochon garnet cut without facets
- carcinogen
- any substance that produces cancer
- card
- thin cardboard, usually rectangular
- cardboard
- a stiff moderately thick paper
- cardiac glucoside
- obtained from a number of plants and used to stimulate the heart in cases of heart failure
- carnallite
- a white or reddish mineral consisting of hydrous chlorides of potassium and magnesium; used as a fertilizer and as a source of potassium and magnesium
- carnelian
- a translucent red or orange variety of chalcedony
- carnotite
- a yellow radioactive mineral; an ore of uranium and radium and vanadium
- carotene
- yellow or orange-red fat-soluble pigments in plants
- carotenoid
- any of a class of highly unsaturated yellow to red pigments occurring in plants and animals
- carrageenan
- a colloidal extract from carrageen seaweed and other red algae
- carrier
- an inactive substance that is a vehicle for a radioactive tracer of the same substance and that assists in its recovery after some chemical reaction
- cartridge brass
- an alloy of copper and zinc (containing about 30% zinc) that is wrought into cartridges or tubing
- cartridge paper
- paper for making cartridge cases
- cartridge paper
- thick white paper for pencil and ink drawings
- case-hardened steel
- steel with a surface that is much harder than the interior metal
- casein
- a milk protein used in making e.g. plastics and adhesives
- casein glue
- made from casein; used for e.g. plywood and cabinetwork
- cashmere
- the wool of the Kashmir goat
- caspase
- any of a group of proteases that mediate apoptosis
- cassava
- a starch made by leaching and drying the root of the cassava plant; the source of tapioca; a staple food in the tropics
- cassiterite
- a hard heavy dark mineral that is the chief source of tin
- cast iron
- an alloy of iron containing so much carbon that it is brittle and so cannot be wrought but must be shaped by casting
- cat's eye
- any of various gems (as chrysoberyl or chalcedony) that reflect light when cut in a rounded shape
- catalase
- enzyme found in most plant and animal cells that functions as an oxidative catalyst; decomposes hydrogen peroxide into oxygen and water
- catechin
- a tannic acid that is extracted from black catechu as a white crystalline substance
- catecholamine
- any of a group of chemicals including epinephrine and norepinephrine that are produced in the medulla of the adrenal gland
- cationic detergent
- a class of synthetic detergents in which the surface-active part of the molecule is the cation
- caulk
- a waterproof filler and sealant that is used in building and repair to make watertight
- caustic
- any chemical substance that burns or destroys living tissue
- caustic potash
- a potassium compound often used in agriculture and industry
- caustic soda
- a strongly alkaline caustic used in manufacturing soap and paper and aluminum and various sodium compounds
- Cd
- a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc ores
- CD4
- a glycoprotein that is found primarily on the surface of helper T cells
- CD8
- a membrane glycoprotein that is found primarily on the surface of cytotoxic T cells
- Ce
- a ductile grey metallic element of the lanthanide series; used in lighter flints; the most abundant of the rare-earth group
- celestite
- a mineral consisting of strontium sulphate
- celluloid
- highly flammable substance made from cellulose nitrate and camphor; used in e.g. motion-picture and X-ray film; its use has decreased with the development of nonflammable thermoplastics
- cellulose
- a polysaccharide that is the chief constituent of all plant tissues and fibers
- cellulose acetate
- an ester of acetic acid; used in fibers and fabrics; photographic films and varnishes
- cellulose ester
- any ester of cellulose with an acid
- cellulose nitrate
- a nitric acid ester; used in lacquers and explosives
- cellulose triacetate
- cellulose acetate that is relatively slow to burn; used instead of celluloid for motion-picture film
- cellulose xanthate
- a cellulose ester obtained by treating cellulose with caustic soda
- cellulosic
- a plastic made from cellulose (or a derivative of cellulose)
- cement
- a building material that is a powder made of a mixture of calcined limestone and clay; used with water and sand or gravel to make concrete and mortar
- cement
- concrete pavement is sometimes referred to as cement
- cement
- any of various materials used by dentists to fill cavities in teeth
- cement
- something that hardens to act as adhesive material
- cementite
- a chemical compound that is a constituent of steel and cast iron; very hard and brittle
- ceratin
- a fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair, feathers, nails, and hooves
- ceresin
- a white wax extracted from ozokerite
- cerotic acid
- a white solid fatty acid found in waxes (such as beeswax)
- cerulean blue
- light greenish-blue pigment consisting essentially of oxides of cobalt and tin
- cerumen
- a soft yellow wax secreted by glands in the ear canal
- ceruse
- a poisonous white pigment that contains lead
- cerussite
- a mineral consisting of lead carbonate that is an important source of lead
- cesium 137
- a radioactive isotope of cesium used in radiation therapy
- cetrimide
- a cationic detergent that is a powerful disinfectant
- Ceylonite
- a dark-colored spinel containing iron
- Cf
- a radioactive transuranic element; discovered by bombarding curium with alpha particles
- CFC
- a fluorocarbon with chlorine; formerly used as a refrigerant and as a propellant in aerosol cans
- chabasite
- a group of minerals of the zeolite family consisting of a hydrous silicate of calcium and aluminum
- chad
- a small piece of paper that is supposed to be removed when a hole is punched in a card or paper tape
- chaff
- material consisting of seed coverings and small pieces of stem or leaves that have been separated from the seeds
- chalcocite
- a heavy grey mineral that is an ore of copper
- chalcopyrite
- a yellow copper ore (CuFeS2) made up of copper and iron sulfide
- chalk
- a soft whitish calcite
- chalk dust
- dust resulting from writing with a piece of chalk
- chalkstone
- a deposit of urates around a joint or in the external ear; diagnostic of advanced or chronic gout
- chalybite
- iron ore in the form of ferrous carbonate
- chammy
- a soft suede leather formerly from the skin of the chamois antelope but now from sheepskin
- chamosite
- a greenish grey or black silicate of iron and aluminum
- char
- a charred substance
- charcoal
- a carbonaceous material obtained by heating wood or other organic matter in the absence of air
- chaulmoogra oil
- an oil from chaulmoogra trees; used in treatment of skin diseases and leprosy
- chelate
- a heterocyclic compound having a metal ion attached by coordinate bonds to at least two nonmetal ions
- chemical agent
- an agent that produces chemical reactions
- chemical compound
- (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight
- chemical element
- any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
- chemical group
- (chemistry) two or more atoms bound together as a single unit and forming part of a molecule
- chemical irritant
- a substance producing irritation
- Chemical Mace
- (trademark) a liquid that temporarily disables a person; prepared as an aerosol and sprayed in the face, it irritates the eyes and causes dizziness and immobilization
- chemical
- material produced by or used in a reaction involving changes in atoms or molecules
- chemistry
- the chemical composition and properties of a substance or object
- cheoplastic metal
- any alloy that fuses at low temperatures and can be used molding artificial teeth
- chernozemic soil
- a rich black loam of Russia
- cherry-tree gum
- exudation from trees of the Prunus genus; resembles gum arabic
- chert
- variety of silica containing microcrystalline quartz
- Chian turpentine
- a turpentine exuded by the terebinth
- chicken manure
- chicken excreta used as fertilizer
- chicle
- gum-like substance from the sapodilla
- china clay
- a fine usually white clay formed by the weathering of aluminous minerals (as feldspar); used in ceramics and as an absorbent and as a filler (e.g., in paper)
- chinchilla
- the expensive silvery grey fur of the chinchilla
- Chinese white
- a white pigment used in house paints; consists of zinc oxide
- Chinese wood oil
- a yellow oil obtained from the seeds of the tung tree
- chipboard
- a cheap hard material made from wood chips that are pressed together and bound with synthetic resin
- chisel steel
- steel used in making chisels
- chitin
- a tough semitransparent horny substance; the principal component of the exoskeletons of arthropods and the cell walls of certain fungi
- chlorate
- any salt of chloric acid
- chloric acid
- (HClO3) a strong unstable acid with an acrid odor found in chlorate salts
- chloride
- any salt of hydrochloric acid (containing the chloride ion)
- chloride
- any compound containing a chlorine atom
- chlorine dioxide
- an explosive gas (ClO2) used chiefly in bleaching paper or starch or soap or flour and in water purification
- chlorine water
- an aqueous solution of chlorine used as a bleaching agent
- chlorite
- a generally green or black mineral; it occurs as a constituent of many rocks typically in the form of a flat crystal
- chlorobenzene
- a colorless volatile flammable liquid with an almond odor that is made from chlorine and benzene; used as a solvent and in the production of phenol and DDT and other organic compounds
- chlorohydric acid
- an aqueous solution of hydrogen chloride; a strongly corrosive acid
- chloropicrin
- a heavy colorless insoluble liquid compound that causes tears and vomiting; used as a pesticide and as tear gas
- chloroprene
- derivative of butadiene used in making neoprene by polymerization
- chlorous acid
- (HClO2) a strongly oxidizing acid; known only in solution
- chlorpyrifos
- a common organophosphate insecticide
- cholesterin
- an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues
- cholic acid
- an insoluble crystalline acid present in bile
- choline
- a B-complex vitamin that is a constituent of lecithin; essential in the metabolism of fat
- cholinesterase
- an enzyme that hydrolyses acetylcholine (into choline and acetic acid)
- chondrin
- a substance that resembles gelatin and is obtained by boiling cartilage in water
- Christmas factor
- coagulation factor whose absence is associated with hemophilia B
- chromate
- any salt or ester of chromic acid
- chrome
- another word for chromium when it is used in dyes or pigments
- chrome alum
- a violet-colored salt used in hide tanning and as a mordant in dyeing
- chrome green
- any of a class of green pigments consisting of chrome yellow and iron blue
- chrome yellow
- any of several yellow pigments consisting of normal lead chromate and other lead compounds
- chrome-tungsten steel
- a steel alloy made with chromium and tungsten
- chromic acid
- an unstable acid known only in solution and as chromate salts
- chromite
- a brownish-black mineral; the major source of chromium
- chromium steel
- steel containing chromium that makes it resistant to corrosion
- chromogen
- a compound that can be converted to a pigment
- chromophore
- the chemical group that gives color to a molecule
- chrysoberyl
- a rare hard yellow green mineral consisting of beryllium aluminate in crystal form; used as a gemstone
- chrysolite
- a brown or yellow-green olivine found in igneous and metamorphic rocks and used as a gemstone
- chrysoprase
- a green variety of chalcedony valued as a gemstone
- chrysotile
- a grey or green fibrous mineral; an important source of commercial asbestos
- chylomicron
- a microscopic particle of triglycerides produced in the intestines during digestion; in the bloodstream they release their fatty acids into the blood
- chyme
- a semiliquid mass of partially digested food that passes from the stomach through the pyloric sphincter into the duodenum
- chymosin
- an enzyme that occurs in gastric juice; causes milk to coagulate
- cigarette paper
- a strong tissue paper that burns evenly and is sufficiently porous to control the burning of the tobacco in a cigarette
- cinchonine
- an alkaloid derivative of the bark of cinchona trees that is used as an antimalarial drug
- cinder pig
- pig iron containing a substantial proportion of slag
- cinnabar
- a heavy reddish mineral consisting of mercuric sulfide; the chief source of mercury
- cinnamene
- a colorless oily liquid; the monomer for polystyrene
- cinnamon stone
- a garnet ranging in color from yellow to brown
- citrate
- a salt or ester of citric acid
- citric acid
- a weak water-soluble acid found in many fruits (especially citrus fruits); used as a flavoring agent
- citrine
- semiprecious yellow quartz resembling topaz
- citrulline
- an amino acid that does not occur in proteins but is an intermediate in the conversion of ornithine to arginine
- Cl
- a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)
- clapboard
- a long thin board with one edge thicker than the other; used as siding by lapping one board over the board below
- clay
- a very fine-grained soil that is plastic when moist but hard when fired
- clay
- water soaked soil; soft wet earth
- claystone
- fine-grained rock consisting of compacted clay particles
- Clorox
- a commercial bleaching agent
- Clostridium perfringens epsilon toxin
- a bacterial toxin produced by clostridium perfringens; causes intense abdominal cramps and diarrhea that begins 8-22 hours after consumption of foods containing large numbers of these bacteria
- clotting factor
- any of the factors in the blood whose actions are essential for blood coagulation
- clove oil
- essential oil obtained from cloves and used to flavor medicines
- clunch
- hardened clay
- Cm
- a radioactive transuranic metallic element; produced by bombarding plutonium with helium nuclei
- CN gas
- a tear gas that is weaker than CS gas but lasts longer
- Co
- a hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition
- CO
- an odorless very poisonous gas that is a product of incomplete combustion of carbon
- CO2
- a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis
- coagulant
- an agent that produces coagulation
- coagulase
- an enzyme that induces coagulation
- coal
- fossil fuel consisting of carbonized vegetable matter deposited in the Carboniferous period
- coal gas
- gaseous mixture produced by distillation of bituminous coal and used for heating and lighting
- coal oil
- a flammable hydrocarbon oil used as fuel in lamps and heaters
- coal tar
- a tar formed from distillation of bituminous coal; coal tar can be further distilled to give various aromatic compounds
- coal-tar creosote
- a dark oily liquid obtained by distillation of coal tar; used as a preservative for wood
- cobalt 60
- a radioactive isotope of cobalt with mass number 60; a source of exceptionally intense gamma rays; used in radiation therapy
- cobalt bloom
- a reddish mineral consisting of hydrated cobalt arsenate in monoclinic crystalline form and used in coloring glass; usually found in veins bearing cobalt and arsenic
- cobalt blue
- greenish-blue pigment consisting essentially of cobalt oxide and alumina
- cobaltite
- a rare silvery-white mineral; important ore of cobalt
- cocarboxylase
- a coenzyme important in respiration in the Krebs cycle
- cochineal
- a red dyestuff consisting of dried bodies of female cochineal insects
- cocoa butter
- a yellow-white fat from cocoa beans
- cod liver oil
- an oil obtained from the livers of cod and similar fishes; taken orally as a source of vitamins A and D
- cod oil
- an inferior cod-liver oil that is used in leather manufacturing
- coding DNA
- sequence of a gene's DNA that transcribes into protein structures
- codon
- a specific sequence of three adjacent nucleotides on a strand of DNA or RNA that specifies the genetic code information for synthesizing a particular amino acid
- coenzyme
- a small molecule (not a protein but sometimes a vitamin) essential for the activity of some enzymes
- coenzyme A
- a coenzyme present in all living cells; essential to metabolism of carbohydrates and fats and some amino acids
- coenzyme Q
- any of several quinones found in living cells and that function as coenzymes that transfer electrons from one molecule to another in cell respiration
- cofactor
- a substance (as a coenzyme) that must join with another to produce a given result
- coin silver
- a silver of the degree of purity established for making legal silver coins
- coke
- carbon fuel produced by distillation of coal
- cold rubber
- a rubber made at low temperatures (5 degrees Centigrade) which is tougher than conventional rubber and is often used in car tires
- collagenase
- any enzyme that catalyzes the hydrolysis of collagen and gelatin
- collodion
- a colorless syrupy solution of pyroxylin in ether and alcohol; used as a coating for wounds or photographic films
- colloid
- a mixture with properties between those of a solution and fine suspension
- colloidal gel
- a colloid in a more solid form than a sol
- colloidal solution
- a colloid that has a continuous liquid phase in which a solid is suspended in a liquid
- colophony
- translucent brittle substance produced from pine oleoresin; used especially in varnishes and inks and on the bows of stringed instruments
- color
- any material used for its color
- coltan
- a valuable black mineral combining niobite and tantalite; used in cell phones and computer chips
- columbite
- a black mineral that is an ore of niobium and tantalum
- columbium
- a former name for niobium
- combustible
- a substance that can be burned to provide heat or power
- common salt
- a white crystalline solid consisting mainly of sodium chloride (NaCl)
- common topaz
- a yellow quartz
- complement
- one of a series of enzymes in the blood serum that are part of the immune response
- complementary DNA
- single-stranded DNA that is complementary to messenger RNA or DNA that has been synthesized from messenger RNA by reverse transcriptase
- complex
- a compound described in terms of the central atom to which other atoms are bound or coordinated
- composite material
- strong lightweight material developed in the laboratory; fibers of more than one kind are bonded together chemically
- composition
- a mixture of ingredients
- compost
- a mixture of decaying vegetation and manure; used as a fertilizer
- compound protein
- a protein complex combining amino acids with other substances
- compressed air
- air at a pressure greater than that of the atmosphere
- compressed gas
- gas at a high pressure that can be used as a propellant
- computer paper
- paper folded to permit continuous printing controlled by a computer
- concentrate
- the desired mineral that is left after impurities have been removed from mined ore
- concrete
- a strong hard building material composed of sand and gravel and cement and water
- condensate
- a product of condensation
- conductor
- a substance that readily conducts e.g. electricity and heat
- congener
- a minor chemical constituent that gives a wine or liquor its distinctive character
- conglomerate
- a composite rock made up of particles of varying size
- congo copal
- copal found usually as a fossil
- congo red
- a red-brown azo dye especially as a chemical pH indicator (congo red is red in basic and blue in acidic solutions)
- conima
- a gum resin from the poison hemlock, Conium maculatum
- conjugate
- a mixture of two partially miscible liquids A and B produces two conjugate solutions: one of A in B and another of B in A
- construction paper
- paper suitable for drawing and making cutouts
- contaminant
- a substance that contaminates
- contrast material
- a substance that is opaque to x-rays; when administered it allows a radiologist to examine the organ or tissue it fills
- coolant
- a fluid agent (gas or liquid) that produces cooling; especially one used to cool a system by transferring heat away from one part to another
- copal
- a brittle aromatic resin used in varnishes
- copaline
- partly mineralized copal dug from the ground
- copolymer
- a polymer consisting of two or more different monomers
- copper oxide
- an oxide of copper
- copper sulfate
- a copper salt made by the action of sulfuric acid on copper oxide
- copper-base alloy
- any alloy whose principal component is copper
- coral
- the hard stony skeleton of a Mediterranean coral that has a delicate red or pink color and is used for jewelry
- cordierite
- a blue mineral of magnesium and iron and aluminum and silicon and oxygen; often used as a gemstone
- cordovan
- a fine leather originally made in Cordoba, Spain
- cordwood
- firewood cut and stacked in cords; wood sold by the cord
- cork
- outer bark of the cork oak; used for stoppers for bottles etc.
- cork
- (botany) outer tissue of bark; a protective layer of dead cells
- corkboard
- a heat-insulating building material consisting of cork granules that are made into sheets by compressing and baking
- corn snow
- granular snow formed by alternate thawing and freezing
- corn sugar
- dextrose made by hydrolysis of cornstarch
- cornflour
- starch prepared from the grains of corn; used in cooking as a thickener
- corrosive
- a substance having the tendency to cause corrosion (such a strong acids or alkali)
- corrugated board
- cardboard with corrugations (can be glued to flat cardboard on one or both sides)
- corticosterone
- secreted by the adrenal cortex; involved in regulating water and electrolyte balance in the body
- Cortone Acetate
- a corticosteroid hormone (trade name Cortone Acetate) normally produced by the adrenal cortex; is converted to hydrocortisone
- corundom
- very hard mineral used as an abrasive
- costus oil
- a yellow volatile essential oil obtained from costusroot; used in perfumes
- cotton cake
- the solid matter remaining after oil has been pressed from cottonseeds
- cotton
- soft silky fibers from cotton plants in their raw state
- coumarone resin
- a thermoplastic resin obtained by polymerization of indene and coumarone; used in coatings and paint and asphalt tile
- counterstain
- a stain of contrasting color that is used when the principal stain does not show the structure clearly
- covering material
- a material used by builders to cover surfaces
- cow manure
- cow excreta used as fertilizer
- cow pie
- fecal matter of a cow
- cowhide
- the hide of a cow
- cowhide
- leather made from the hide of a cow
- Cox
- either of two related enzymes that control the production of prostaglandins and are blocked by aspirin
- Cox-1
- an enzyme that regulates prostaglandins that are important for the health of the stomach lining and kidneys
- Cox-2
- an enzyme that makes prostaglandins that cause inflammation and pain and fever
- Cr
- a hard brittle multivalent metallic element; resistant to corrosion and tarnishing
- crackling
- the residue that remains after animal fat has been rendered
- crap
- obscene terms for feces
- Crazy Glue
- a commercial brand of epoxy glue
- cream of tartar
- a salt used especially in baking powder
- creatin
- an amino acid that does not occur in proteins but is found in the muscle tissue of vertebrates both in the free form and as phosphocreatine; supplies energy for muscle contraction
- creatine phosphate
- an organic compound of creatine and phosphoric acid; found in the muscles of vertebrates where its hydrolysis releases energy for muscular contraction
- creosol
- a colorless to yellow aromatic liquid that is a constituent of creosote
- creosote
- a colorless or yellowish oily liquid obtained by distillation of wood tar; used as an antiseptic
- crepe rubber
- crude natural rubber; used mainly for shoe soles
- crepe
- paper with a crinkled texture; usually colored and used for decorations
- cresol
- any of three poisonous colorless isomeric phenols; derived from coal or wood tar; used as a disinfectant
- cristobalite
- a white mineral consisting of silica; found in volcanic rocks
- crocolite
- a rare lead chromite mineral that forms bright orange crystals
- crown glass
- a glass blown into a globe which is later flattened and spun to form a disk
- crown glass
- optical glass of low dispersion and low refractive index
- crucible steel
- steel made by the mixture of molten wrought iron, charcoal, and other substances in a crucible
- crud
- heavy wet snow that is unsuitable for skiing
- crud
- any substance considered disgustingly foul or unpleasant
- crude
- a dark oil consisting mainly of hydrocarbons
- crush
- leather that has had its grain pattern accentuated
- crushed rock
- rock fragments and pebbles
- cryogen
- a liquid that boils at below -160 C and is used as a refrigerant
- crystal
- a solid formed by the solidification of a chemical and having a highly regular atomic structure
- crystal violet
- a green crystal (violet in water) used as a dye or stain or bactericide or fungicide or anthelmintic or burn treatment
- crystal
- colorless glass made of almost pure silica
- Cs
- a soft silver-white ductile metallic element (liquid at normal temperatures); the most electropositive and alkaline metal
- CS gas
- a tear gas that is stronger than CN gas but wears off faster; can be deployed by grenades or cluster bombs; can cause skin burns and fatal pulmonary edema
- Cu
- a ductile malleable reddish-brown corrosion-resistant diamagnetic metallic element; occurs in various minerals but is the only metal that occurs abundantly in large masses; used as an electrical and thermal conductor
- culture medium
- (bacteriology) a nutrient substance (solid or liquid) that is used to cultivate micro-organisms
- cupric acetate
- a blue or green powder used as a paint pigment
- cuprite
- a mineral consisting of cuprous oxide that is a source of copper
- cupronickel
- a 60/40 alloy of copper and nickel
- curare
- a toxic alkaloid found in certain tropical South American trees that is a powerful relaxant for striated muscles
- cutin
- (biochemistry) a waxy transparent material that occurs in the cuticle of plants and consists of highly polymerized esters of fatty acids
- cyanamid
- a weak soluble dibasic acid (the parent acid of cyanamide salts)
- cyanic acid
- a colorless poisonous volatile liquid acid that hydrolyzes readily to ammonia and carbon dioxide
- cyanide
- an extremely poisonous salt of hydrocyanic acid
- cyanide group
- the monovalent group -CN in a chemical compound
- cyanide
- any of a class of organic compounds containing the cyano radical -CN
- cyanine dye
- any of a class of dyes containing a -CH= group linking two heterocyclic rings containing nitrogen; used as sensitizers in photography
- cyanite
- a grey or greenish-blue mineral consisting of aluminum silicate in crystalline form; occurs in metaphoric rock, used as a refractory
- cyanogen
- a colorless toxic gas with a pungent almond odor; has been used in chemical warfare
- cyanohydrin
- any organic compound in which the cyano radical -CN and the hydroxyl radical -OH are attached to the same carbon atom
- cyanuramide
- a white crystalline organic base; used mainly in making melamine resins
- cyanuric acid
- a trimer of cyanic acid
- cyclohexanol
- a colorless oily alcohol that smells like camphor
- cyclohexanol phthalate
- the cyclohexanol ester of phthalic acid
- cymene
- any of three isotopes of a colorless aromatic liquid hydrocarbon occurring in the volatile oil of cumin and thyme and used in the manufacture of synthetic resins
- cysteine
- an amino acid containing sulfur that is found in most proteins; oxidizes on exposure to air to form cystine
- cystine
- a crystalline amino acid found in proteins (especially keratin); discovered in bladder stones
- cytidine
- a nucleoside component of DNA; composed of cytosine and deoxyribose
- cytochrome
- (biochemistry) a class of hemoprotein whose principal biological function is electron transfer (especially in cellular respiration)
- cytochrome c
- the most abundant and stable cytochrome; involved in energy transfer
- cytokine
- any of various protein molecules secreted by cells of the immune system that serve to regulate the immune system
- cytokinin
- any of a class of plant hormones that promote cell division and delay the senescence of leaves
- cytolysin
- a substance that partly or completely destroys animal cells
- cytotoxin
- any substance that has a toxic effect on cells
- dacite
- a grey volcanic rock containing plagioclase and quartz and other crystalline minerals
- damar
- any of various hard resins from trees of the family Dipterocarpaceae and of the genus Agathis; especially the amboyna pine
- Damascus steel
- a hard resilient steel often decorated and used for sword blades
- damourite
- a variety of muscovite
- dark matter
- (cosmology) a hypothetical form of matter that is believed to make up 90 percent of the universe; it is invisible (does not absorb or emit light) and does not collide with atomic particles but exerts gravitational force
- daub
- material used to daub walls
- Davy's grey
- slightly purplish or bluish dark grey
- Db
- a transuranic element
- DDT
- an insecticide that is also toxic to animals and humans; banned in the United States since 1972
- de-iodinase
- an enzyme that removes the iodine radical
- DEAE cellulose
- used for chromatography
- deal
- a plank of softwood (fir or pine board)
- deal
- wood that is easy to saw (from conifers such as pine or fir)
- debris
- the remains of something that has been destroyed or broken up
- decanedioic acid
- a dicarboxylic acid used to make resins
- decarboxylase
- any of the enzymes that hydrolize the carboxyl group
- deerskin
- leather from the hide of a deer
- defoliant
- a chemical that is sprayed on plants and causes their leaves to fall off
- delta iron
- an allotrope of iron that is stable between 1403 degrees centigrade and the melting point (= 1532 degrees)
- demantoid
- a green andradite used as a gemstone
- demerara
- a light brown raw cane sugar from Guyana
- denaturant
- any substance that serves as a denaturing agent
- denatured alcohol
- ethyl alcohol that is unfit for drinking but is still useful for other purposes
- dental gold
- an alloy of gold used in dentistry
- dentin
- a calcareous material harder and denser than bone that comprises the bulk of a tooth
- deoxyadenosine
- a nucleoside component of DNA; composed of adenosine and deoxyribose
- deoxyguanosine
- a nucleoside component of DNA; composed of guanine and deoxyribose
- deoxyribose
- a sugar that is a constituent of nucleic acids
- deoxythymidine
- a nucleoside component of DNA; composed of thymine and deoxyribose
- depilatory
- a chemical (usually a sulfide) used to remove hair or wool or bristles from hides
- derivative
- a compound obtained from, or regarded as derived from, another compound
- derv
- diesel oil used in cars and lorries with diesel engines; from d(iesel) e(ngine) r(oad) v(ehicle)
- DES
- a potent estrogen used in medicine and in feed for livestock and poultry
- desert soil
- a type of soil that develops in arid climates
- desiccant
- a substance that promotes drying (e.g., calcium oxide absorbs water and is used to remove moisture)
- detergent
- a surface-active chemical widely used in industry and laundering
- detritus
- loose material (stone fragments and silt etc) that is worn away from rocks
- deuterium oxide
- water containing a substantial proportion of deuterium atoms, used in nuclear reactors
- deuterium
- an isotope of hydrogen which has one neutron (as opposed to zero neutrons in hydrogen)
- dew
- water that has condensed on a cool surface overnight from water vapor in the air
- Dexamethasone Intensol
- a corticosteroid drug (trade names Decadron or Dexamethasone Intensol or Dexone or Hexadrol or Oradexon) used to treat allergies or inflammation
- dextrin
- any of various polysaccharides obtained by hydrolysis of starch; a tasteless and odorless gummy substance that is used as a thickening agent and in adhesives and in dietary supplements
- dextroglucose
- an isomer of glucose that is found in honey and sweet fruits
- di-iodotyrosine
- tyrosine with two iodine atoms added
- diamagnet
- a substance that exhibits diamagnetism
- diamine
- any organic compound containing two amino groups
- diatomaceous earth
- a light soil consisting of siliceous diatom remains and often used as a filtering material
- diazonium
- the univalent cation R-N:N- (where R is an aromatic hydrocarbon); found in salts that are used in manufacturing azo dyes
- dibasic acid
- an acid containing two replaceable hydrogen atoms per molecule
- dibasic salt
- a salt derived by replacing two hydrogen atoms per molecule
- dichloromethane
- a nonflammable liquid used as a solvent and paint remover and refrigerant
- dichromic acid
- the hypothetical acid (H2Cr2O7) from which dichromates are derived; known only in solution and in the form of dichromate salts
- dielectric
- a material such as glass or porcelain with negligible electrical or thermal conductivity
- diesel fuel
- a heavy mineral oil used as fuel in diesel engines
- digestive
- any substance that promotes digestion
- digitalin
- a powerful cardiac stimulant obtained from foxglove
- dihydric alcohol
- any of a class of alcohols having 2 hydroxyl groups in each molecule
- dihydroxyphenylalanine
- amino acid that is formed in the liver and converted into dopamine in the brain
- diluent
- a diluting agent
- dilution
- a diluted solution
- dimer
- a compound whose molecules are composed of two identical monomers
- dimethylglyoxime
- a compound used in analysis as a precipitant for palladium or nickel
- dimple
- a chad that has been punched or dimpled but all four corners are still attached
- diorite
- a granular crystalline intrusive rock
- dioxide
- an oxide containing two atoms of oxygen in the molecule
- dioxin
- any of several toxic or carcinogenic hydrocarbons that occur as impurities in herbicides
- Dippel's oil
- dark-colored ill-smelling oil obtained by carbonizing bone; used especially in sheep dips and in denaturing alcohol
- direct dye
- dye with a high affinity for cellulose fibers (cotton or rayon etc.)
- dirt
- the part of the earth's surface consisting of humus and disintegrated rock
- disaccharidase
- an enzyme that catalyzes the hydrolysis of disaccharides into monosaccharides
- disaccharide
- any of a variety of carbohydrates that yield two monosaccharide molecules on complete hydrolysis
- discharge
- a substance that is emitted or released
- dishwater
- water in which dishes and cooking utensils are washed
- dispersed particles
- (of colloids) a substance in the colloidal state
- dispersing medium
- (of colloids) a substance in which another is colloidally dispersed
- dissolvent
- a liquid substance capable of dissolving other substances
- distillate
- a purified liquid produced by condensation from a vapor during distilling; the product of distilling
- distilled water
- water that has been purified by distillation
- DNA
- (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information
- DNA polymerase
- the enzyme responsible for DNA replication
- docosahexaenoic acid
- an omega-3 fatty acid with 22 carbon atoms; found in fish (especially tuna and bluefish)
- dodecanoic acid
- a crystalline fatty acid occurring as glycerides in natural fats and oils (especially coconut oil and palm-kernel oil)
- doeskin
- soft leather from deerskin or lambskin
- dolomite
- a kind of sedimentary rock resembling marble or limestone but rich in magnesium carbonate
- dolphin oil
- an unsaturated fatty oil obtained from dolphins and used as a fine lubricant
- domoic acid
- a neurotoxin that is deadly for humans; found in various marine algae
- dottle
- the residue of partially burnt tobacco left caked in the bowl of a pipe after smoking
- double salt
- a solution of two simple salts that forms a single substance on crystallization
- dragon's blood
- a dark red resinous substance derived from various trees and used in photoengraving
- drawing paper
- paper that is specially prepared for use in drafting
- driftwood
- wood that is floating or that has been washed ashore
- drill rod
- carbon steel used for rock drills and dowels
- drilling fluid
- a mixture of clays and chemicals and water; pumped down the drill pipe to lubricate and cool the drilling bit and to flush out the cuttings and to strengthen the sides of the hole
- dripstone
- the form of calcium carbonate found in stalactites and stalagmites
- droppings
- fecal matter of animals
- dross
- worthless or dangerous material that should be removed
- dross
- the scum formed by oxidation at the surface of molten metals
- dry ice
- solidified carbon dioxide; dry ice sublimates at -78.5 C and is used mainly as a refrigerant
- drying oil
- an oil that hardens in air due to oxidation and is often used as a paint or varnish base
- Ds
- a radioactive transuranic element
- dscDNA
- double-stranded cDNA
- dubbin
- tallow mixed with oil; used to make leather soft and waterproof
- Durabolin
- an androgen (trade names Durabolin or Kabolin) that is used to treat testosterone deficiency or breast cancer or osteoporosis
- Duralumin
- an aluminum-based alloy
- dust
- fine powdery material such as dry earth or pollen that can be blown about in the air
- dust
- free microscopic particles of solid material
- Dy
- a trivalent metallic element of the rare earth group; forms compounds that are highly magnetic
- dye
- a usually soluble substance for staining or coloring e.g. fabrics or hair
- dyewood
- any wood from which dye is obtained
- earth
- once thought to be one of four elements composing the universe (Empedocles)
- earth color
- a colored mineral used as a pigment
- earth
- the loose soft material that makes up a large part of the land surface
- eau de Javelle
- an aqueous solution of sodium hypochlorite
- ebonite
- a hard nonresilient rubber formed by vulcanizing natural rubber
- ectoplasm
- (spiritualism) a substance supposed to emanate from the body of the medium during a trance
- EDTA
- a complex molecule used medically to chelate metal ions in cases of lead or heavy metal poisoning
- effluent
- water mixed with waste matter
- effluvium
- a foul-smelling outflow or vapor (especially a gaseous waste)
- eicosapentaenoic acid
- an omega-3 fatty acid with 20 carbon atoms; found in fish (especially tuna and bluefish)
- elaeostearic acid
- a crystalline unsaturated fatty acid
- elaidic acid
- a monounsaturated fatty acid that has the same structure as oleic acid except that it is a trans fatty acid; the major trans fatty acid in margarine and fried foods
- elastase
- a pancreatic enzyme that catalyzes the hydrolysis of elastin
- elastomer
- any of various elastic materials that resemble rubber (resumes its original shape when a deforming force is removed)
- electrolyte
- a solution that conducts electricity
- electrum
- an alloy of gold and silver
- element
- one of four substances thought in ancient and medieval cosmology to constitute the physical universe
- Elinvar
- Elinvar is a trademark for a kind of steel used for watch springs because its elasticity is constant over a wide range of temperatures
- elixir
- a sweet flavored liquid (usually containing a small amount of alcohol) used in compounding medicines to be taken by mouth in order to mask an unpleasant taste
- elixir
- hypothetical substance that the alchemists believed to be capable of changing base metals into gold
- eluate
- a liquid solution that results from elution
- emanation
- something that is emitted or radiated (as a gas or an odor or a light, etc.)
- emerald
- a green transparent form of beryl; highly valued as a gemstone
- emery
- a hard grey-black mineral consisting of corundum and either hematite or magnetite; used as an abrasive (especially as a coating on paper)
- emery cloth
- cloth covered with powdered emery
- emery paper
- stiff paper coated with powdered emery or sand
- emery rock
- a mixture of emery dust and a binder; can be molded into grindstones
- emmenagogue
- any agent that promotes menstrual discharge
- emulsifier
- a surface-active agent that promotes the formation of an emulsion
- emulsion
- (chemistry) a colloid in which both phases are liquids
- enamel
- a colored glassy compound (opaque or partially opaque) that is fused to the surface of metal or glass or pottery for decoration or protection
- enamine
- an amine containing the double bond linkage -C=C-N-
- enantiomer
- either one of a pair of compounds (crystals or molecules) that are mirror images on each other but are not identical
- endonuclease
- a nuclease that cleaves nucleic acids at interior bonds and so produces fragments of various sizes
- endorphin
- a neurochemical occurring naturally in the brain and having analgesic properties
- endotoxin
- a toxin that is confined inside the microorganisms and is released only when the microorganisms are broken down or die
- enkephalin
- an endorphin having opiate qualities that occurs in the brain and spinal cord and elsewhere
- enol
- an organic compound that contains a hydroxyl group bonded to a carbon atom which in turn is doubly bonded to another carbon atom
- enterokinase
- enzyme in the intestinal juice that converts inactive trypsinogen into active trypsin
- enterotoxin
- a cytotoxin specific for the cells of the intestinal mucosa
- enzyme
- any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions
- ephedrine
- white odorless powdered or crystalline alkaloid from plants of the genus Ephedra (especially Ephedra sinica) or made synthetically; used as a bronchodilator to treat bronchitis and asthma
- episome
- DNA that is not incorporated into the genome but is replicated together with the genome (especially in bacterial cells)
- epoxy
- a thermosetting resin; used chiefly in strong adhesives and coatings and laminates
- Epsom salts
- hydrated magnesium sulfate that is taken orally to treat heartburn and constipation and injected to prevent seizures
- Er
- a trivalent metallic element of the rare earth group; occurs with yttrium
- ergosterol
- a plant sterol that is converted into vitamin D by ultraviolet radiation
- ergotamine
- an alkaloid derived from ergot that is less toxic than ergot; causes constriction of blood vessels and is used to treat migraine
- Ergotrate Maleate
- an alkaloid derived from ergot (trade name Ergotrate Maleate) that is less toxic than ergot; induces muscular contraction of the uterus and is administered after childbirth or abortion
- ermine
- the expensive white fur of the ermine
- erythrocytolysin
- any substance that can cause lysis (destruction) of erythrocytes (red blood cells) and the release of their hemoglobin
- erythropoietin
- a glycoprotein secreted by the kidneys that stimulates the production of red blood cells
- Es
- a radioactive transuranic element produced by bombarding plutonium with neutrons
- essence
- any substance possessing to a high degree the predominant properties of a plant or drug or other natural product from which it is extracted
- essential amino acid
- an amino acid that is required by animals but that they cannot synthesize; must be supplied in the diet
- essential oil
- an oil having the odor or flavor of the plant from which it comes; used in perfume and flavorings
- ester
- organic compound formed by reaction between an acid and an alcohol with elimination of water
- estradiol
- the most powerful female hormone that occurs naturally; synthesized and used to treat estrogen deficiency and breast cancer
- estriol
- a naturally occurring estrogenic hormone; a synthetic form is used to treat estrogen deficiency
- estrogen
- a general term for female steroid sex hormones that are secreted by the ovary and responsible for typical female sexual characteristics
- Estronol
- a naturally occurring weak estrogenic hormone secreted by the mammalian ovary; synthesized (trade name Estronol) and used to treat estrogen deficiency
- ethanal trimer
- a colorless liquid (a cyclic trimer of acetaldehyde) that is used as a sedative and a solvent
- ethanedioic acid
- a toxic colorless crystalline organic acid found in oxalis and other plants; used as a bleach and rust remover and in chemical analysis
- ethanediol
- a sweet but poisonous syrupy liquid used as an antifreeze and solvent
- ethanol
- the intoxicating agent in fermented and distilled liquors; used pure or denatured as a solvent or in medicines and colognes and cleaning solutions and rocket fuel; proposed as a renewable clean-burning additive to gasoline
- ethene
- a flammable colorless gaseous alkene; obtained from petroleum and natural gas and used in manufacturing many other chemicals; sometimes used as an anesthetic
- ether
- any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom
- ether
- the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies
- ethyl acetate
- a fragrant colorless flammable volatile liquid ester made from ethanol and acetic acid; used in flavorings and perfumes and as a solvent for plastics
- ethyl
- the univalent hydrocarbon radical C2H5 derived from ethane by the removal of one hydrogen atom
- Eu
- a bivalent and trivalent metallic element of the rare earth group
- eucalyptus oil
- an essential oil obtained from the leaves of eucalypts
- euphorbium
- an acrid brown gum resin now used mainly in veterinary medicine
- Eureka
- an alloy of copper and nickel with high electrical resistance and a low temperature coefficient; used as resistance wire
- eutectic
- a mixture of substances having a minimum melting point
- eutectoid steel
- a steel that contains 0.9% carbon (the eutectic point); a carbon steel with 0.9% carbon is pure pearlite
- evaporite
- the sediment that is left after the evaporation of seawater
- excelsior
- thin curly wood shavings used for packing or stuffing
- exhalation
- exhaled breath
- exhaust
- gases ejected from an engine as waste products
- exonuclease
- a nuclease that releases one nucleotide at a time (serially) beginning at one of a nucleic acid
- exotherm
- a compound that gives off heat during its formation and absorbs heat during its decomposition
- exotoxin
- a toxin that is secreted by microorganisms into the surrounding medium
- extract
- a solution obtained by steeping or soaking a substance (usually in water)
- extravasation
- an extravasated liquid (blood or lymph or urine); the product of extravasation
- exudate
- a substance that oozes out from plant pores
- F
- a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite
- facial tissue
- tissue paper suitable for use on the face
- factor I
- a protein present in blood plasma; converts to fibrin when blood clots
- factor II
- a protein in blood plasma that is the inactive precursor of thrombin
- factor III
- an enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot
- factor IV
- ion of calcium; a factor in the clotting of blood
- factor V
- a coagulation factor
- factor VII
- a coagulation factor formed in the kidney under the influence of vitamin K
- factor VIII
- a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A
- factor X
- coagulation factor that is converted to an enzyme that converts prothrombin to thrombin in a reaction that depends on calcium ions and other coagulation factors
- factor XI
- coagulation factor whose deficiency results in a hemorrhagic tendency
- factor XIII
- in the clotting of blood thrombin catalyzes factor XIII into its active form (fibrinase) which causes fibrin to form a stable clot
- fallout
- the radioactive particles that settle to the ground after a nuclear explosion
- fat
- a soft greasy substance occurring in organic tissue and consisting of a mixture of lipids (mostly triglycerides)
- fat-soluble vitamin
- any vitamin that is soluble in fats
- fatty acid
- any of a class of aliphatic monocarboxylic acids that form part of a lipid molecule and can be derived from fat by hydrolysis; fatty acids are simple molecules built around a series of carbon atoms linked together in a chain of 12 to 22 carbon atoms
- fatty oil
- nonvolatile animal or plant oil
- Fe
- a heavy ductile magnetic metallic element; is silver-white in pure form but readily rusts; used in construction and tools and armament; plays a role in the transport of oxygen by the blood
- fecula
- excreta (especially of insects)
- feedstock
- the raw material that is required for some industrial process
- Fehling's solution
- a liquid solution of copper sulfate and potassium tartrate and sodium hydroxide that is used to test for sugar in the urine; solution turns reddish when sugar is present
- feldspar
- any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium
- fell
- the dressed skin of an animal (especially a large animal)
- fencing
- material for building fences
- fergusonite
- a dark mineral consisting of oxides of yttrium and erbium and tantalum and other minerals
- ferment
- a substance capable of bringing about fermentation
- ferric oxide
- a red oxide of iron
- ferricyanic acid
- a brown unstable acid formed from ferricyanide
- ferricyanide
- salt of ferricyanic acid obtained by oxidation of a ferrocyanide
- ferrite
- a solid solution in which alpha iron is the solvent
- ferritin
- a protein containing 20% iron that is found in the intestines and liver and spleen; it is one of the chief forms in which iron is stored in the body
- ferrocerium
- a pyrophoric alloy of iron with cerium; used for lighter flints
- ferroconcrete
- concrete with metal and/or mesh added to provide extra support against stresses
- ferrocyanic acid
- a white unstable acid formed from ferrocyanide salts
- ferrocyanide
- salt of ferrocyanic acid usually obtained by a reaction of a cyanide with iron sulphate
- fertiliser
- any substance such as manure or a mixture of nitrates used to make soil more fertile
- fetoprotein
- any of several antigens that occur naturally in the fetus and sometimes in adults with cancer
- fiber
- a slender and greatly elongated substance capable of being spun into yarn
- fiberglass
- a covering material made of glass fibers in resins
- fibril
- a very slender natural or synthetic fiber
- fibrin
- a white insoluble fibrous protein formed by the action of thrombin on fibrinogen when blood clots; it forms a network that traps red cells and platelets
- fibrinolysin
- an enzyme that dissolves the fibrin of blood clots
- fibrinopeptide
- peptide released from the amino end of fibrinogen by the action of thrombin to form fibrin during clotting of the blood
- fieldstone
- stone that occurs naturally in fields; often used as building material
- fig wax
- a hard cream-colored wax obtained from a Javanese fig tree
- filaggrin
- the main protein of the keratohyalin granules
- fill
- any material that fills a space or container
- filler
- used for filling cracks or holes in a surface
- filter paper
- a porous unsized paper used for filtering
- filtrate
- the product of filtration; a gas or liquid that has been passed through a filter
- fire
- once thought to be one of four elements composing the universe (Empedocles)
- fire
- fuel that is burning and is used as a means for cooking
- fire opal
- an opal with flaming orange and yellow and red colors
- fireclay
- a heat-resistant clay
- firedamp
- a mixture of gases (mostly methane) that form in coal mines and become explosive when mixed with air
- firelighter
- (a piece of) a substance that burns easily and can be used to start a coal or coke fire
- firestone
- a piece of flint that is struck to light a fire
- firewood
- wood used for fuel
- fish glue
- gelatinous substance obtained by boiling skins fins and bones of fish
- fish meal
- ground dried fish used as fertilizer and as feed for domestic livestock
- fish oil
- a fatty oil obtained from the livers of various fish
- fixative
- a compound (such as ethanol or formaldehyde) that fixes tissues and cells for microscopic study
- fixer
- a chemical compound that sets or fixes something (as a dye or a photographic image)
- flavin
- a ketone that forms the nucleus of certain natural yellow pigments like riboflavin
- flavone
- a colorless crystalline compound that is part of a number of white or yellow plant pigments
- flavonoid
- any of a large class of plant pigments having a chemical structure based on or similar to flavone
- flax
- fiber of the flax plant that is made into thread and woven into linen fabric
- Flaxedil
- neuromuscular blocking agent (trade name Flaxedil) used as a muscle relaxant in the administration of anesthesia
- flaxseed oil
- a drying oil extracted from flax seed and used in making such things as oil paints
- flaxseed
- the seed of flax used as a source of oil
- fleece
- the wool of a sheep or similar animal
- fleece
- tanned skin of a sheep with the fleece left on; used for clothing
- flimsy
- a thin strong lightweight translucent paper used especially for making carbon copies
- flint
- a hard kind of stone; a form of silica more opaque than chalcedony
- flint glass
- optical glass of high dispersion and high refractive index
- flintstone
- pebbles of flint used in masonry construction
- floc
- a small loosely aggregated mass of flocculent material suspended in or precipitated from a liquid
- floor wax
- a preparation containing wax and used to polish and preserve the finish of floors
- flooring
- building material used in laying floors
- flowers of zinc
- oxide of zinc; a white powder used as a pigment or in cosmetics or glass or inks and in zinc ointment
- fluff
- any light downy material
- fluid
- a substance that is fluid at room temperature and pressure
- fluid
- continuous amorphous matter that tends to flow and to conform to the outline of its container: a liquid or a gas
- fluor
- a soft mineral (calcium fluoride) that is fluorescent in ultraviolet light; chief source of fluorine
- fluorapatite
- a form of apatite in which fluorine predominates over chlorine
- fluorescein isocyanate
- a fluorochrome commonly conjugated with antibodies for use in indirect immunofluorescence
- fluorescein
- a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)
- fluoride
- a salt of hydrofluoric acid
- fluoroboric acid
- an acid of fluorine and boron
- fluoroboride
- a salt of fluoroboric acid
- fluorocarbon
- a halocarbon in which some hydrogen atoms have been replaced by fluorine; used in refrigerators and aerosols
- fluorocarbon plastic
- a plastic made with fluorocarbon
- fluorochrome
- any of various fluorescent substances used in fluorescence microscopy to stain specimens
- fluoroform
- colorless gas haloform CHF3 (similar to chloroform)
- fluosilicate
- salt of fluosilicic acid
- fluosilicic acid
- an unstable poisonous corrosive acid known primarily in the form of its salts
- flux
- a substance added to molten metals to bond with impurities that can then be readily removed
- fly ash
- fine solid particles of ash that are carried into the air when fuel is combusted
- flypaper
- paper that is poisoned or coated with a sticky substance to kill flies
- flyspeck
- a tiny dark speck made by the excrement of a fly
- Fm
- a radioactive transuranic metallic element produced by bombarding plutonium with neutrons
- foam
- a lightweight material in cellular form; made by introducing gas bubbles during manufacture
- foam rubber
- spongy rubber; made by introducing air bubbles before vulcanization and used for cushioning or upholstery
- fomentation
- a substance used as a warm moist medicinal compress or poultice
- food waste
- food that is discarded (as from a kitchen)
- fool's gold
- a common mineral (iron disulfide) that has a pale yellow color
- formaldehyde
- a colorless poisonous gas; made by the oxidation of methanol
- formalin
- a 10% solution of formaldehyde in water; used as a disinfectant or to preserve biological specimens
- formic acid
- a colorless pungent fuming vesicatory liquid acid HCOOH found naturally in ants and many plants or made catalytically from carbon monoxide and steam; used in finishing textiles and paper and in the manufacture of insecticides and fumigants
- formulation
- a substance prepared according to a formula
- Forssman antibody
- an antibody found in the blood of someone suffering from infectious mononucleosis
- foryml
- (chemistry) the negative univalent acyl radical CHO that occurs in aldehydes
- fossil fuel
- fuel consisting of the remains of organisms preserved in rocks in the earth's crust with high carbon and hydrogen content
- fox
- the grey or reddish-brown fur of a fox
- Fr
- a radioactive element of the alkali-metal group discovered as a disintegration product of actinium
- fraction
- a component of a mixture that has been separated by a fractional process
- frankincense
- an aromatic gum resin obtained from various Arabian or East African trees; formerly valued for worship and for embalming and fumigation
- free radical
- an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule
- freezing mixture
- a mixture of substances (usually salt and ice) to obtain a temperature below the freezing point of water
- French chalk
- a soft white compact talc used to mark cloth or to remove grease stains
- French ultramarine blue
- ultramarine pigment prepared artificially
- Freon
- any one or more chlorofluorocarbons (or related compounds) that are used as an aerosol propellant, organic solvent, or refrigerant
- fresh water
- water that is not salty
- frost
- ice crystals forming a white deposit (especially on objects outside)
- fructose
- a simple sugar found in honey and in many ripe fruits
- FSH
- a gonadotropic hormone that is secreted by the anterior pituitary and stimulates growth of Graafian follicles in female mammals, and activates the cells in male mammals that form sperm
- fuel
- a substance that can be consumed to produce energy
- fuel oil
- a petroleum product used for fuel
- fuller's earth
- an absorbent soil resembling clay; used in fulling (shrinking and thickening) woolen cloth and as an adsorbent
- fullerene
- a form of carbon having a large molecule consisting of an empty cage of sixty or more carbon atoms
- fulminate
- a salt or ester of fulminic acid
- fulminate of mercury
- a fulminate that when dry explodes violently if struck or heated; used in detonators and blasting caps and percussion caps
- fulminic acid
- (CNOH) an unstable acid occurring mainly in the form of explosive salts and esters that is isomeric with cyanic acid
- fulvic acid
- a yellow to yellow-brown humic substance that is soluble in water under all pH conditions
- fumaric acid
- a colorless crystalline acid with a fruity taste; used in making polyester resins
- fumigant
- a chemical substance used in fumigation
- fur
- the dressed hairy coat of a mammal
- furan
- a colorless toxic flammable liquid used in the synthesis of nylon
- furfural
- a liquid aldehyde with a penetrating odor; made from plant hulls and corncobs; used in making furan and as a solvent
- fusel oil
- a mixture of amyl alcohols and propanol and butanol formed from distillation of fermented liquors
- fusible metal
- an alloy with a low melting point and used as solder and in safety plugs and sprinkler fuses
- G
- a purine base found in DNA and RNA; pairs with cytosine
- G
- one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
- Ga
- a rare silvery (usually trivalent) metallic element; brittle at low temperatures but liquid above room temperature; occurs in trace amounts in bauxite and zinc ores
- GA
- the first known nerve agent, synthesized by German chemists in 1936; a highly toxic combustible liquid that is soluble in organic solvents and is used as a nerve gas in chemical warfare
- GABA
- an amino acid that is found in the central nervous system; acts as an inhibitory neurotransmitter
- gabbro
- one of a family of granular intrusive rocks
- gadolinite
- a mineral that is a source of rare earths; consists of silicates of iron and beryllium and cerium and yttrium and erbium
- galactagogue
- agent that induces milk secretion
- galbanum
- a bitter aromatic gum resin that resembles asafetida
- galena
- soft blue-grey mineral; lead sulfide; a major source of lead
- gallic acid
- a colorless crystalline acid obtained from tannin
- galvanized iron
- iron that is coated with zinc to protect it from rust
- gamboge
- a gum resin used as a yellow pigment and a purgative
- gamma acid
- a crystalline acid used to make azo dyes
- gamma globulin
- a plasma protein containing the immunoglobulins that are responsible for immune responses
- gamma iron
- a nonmagnetic allotrope of iron that is the basis of austenite; stable between 906 and 1403 degrees centigrade
- gargle
- a medicated solution used for gargling and rinsing the mouth
- garnet
- any of a group of hard glassy minerals (silicates of various metals) used as gemstones and as an abrasive
- garnet lac
- lac refined by treating with solvent; garnet-colored
- garnierite
- a green mineral consisting of hydrated nickel magnesium silicate; a source of nickel
- gas
- a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely
- gas oil
- an oil formed through distillation of petroleum of intermediate boiling range and viscosity
- gas
- a volatile flammable mixture of hydrocarbons (hexane and heptane and octane etc.) derived from petroleum; used mainly as a fuel in internal-combustion engines
- gas
- a fossil fuel in the gaseous state; used for cooking and heating homes
- gasohol
- a gasoline substitute consisting of 90% gasoline and 10% grain alcohol from corn
- GB
- a highly toxic chemical nerve agent that inhibits the activity of cholinesterase
- Gd
- a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group
- GD
- a nerve agent easily absorbed into the body; a lethal cholinesterase inhibitor that is highly toxic when inhaled
- Ge
- a brittle grey crystalline element that is a semiconducting metalloid (resembling silicon) used in transistors; occurs in germanite and argyrodite
- gelatin
- a colorless water-soluble glutinous protein obtained from animal tissues such as bone and skin
- gem
- a crystalline rock that can be cut and polished for jewelry
- German silver
- a silver-white alloy containing copper and zinc and nickel
- germanite
- a rare reddish-grey mineral consisting of a copper iron germanium sulfide
- gesso
- gypsum or plaster of Paris spread on a surface to make it suitable for painting or gilding (or a surface so prepared)
- ghatti
- an Indian gum from the dhawa tree; used as a substitute for gum arabic
- Ghedda wax
- wax from Indian and African bees
- GHRF
- a releasing factor that accelerates the secretion of growth hormone by the anterior pituitary body
- gibberellic acid
- a crystalline acid associated with gibberellin
- gibberellin
- a plant hormone isolated from a fungus; used in promoting plant growth
- gibbsite
- white crystalline mineral consisting of aluminum hydroxide; a constituent of bauxite and a source of alumina
- gift wrap
- attractive wrapping paper suitable for wrapping gifts
- gilding metal
- a brass that is rich in copper; used to make articles that were to be gilded
- gilgai soil
- soil in the melon holes of Australia
- gingerol
- derived from ginger; source of the hotness of ginger
- glass
- a brittle transparent solid with irregular atomic structure
- glass wool
- glass fibers spun and massed into bundles resembling wool
- Glauber's salts
- (Na2SO4.10H2O) a colorless salt used as a cathartic
- glauconite
- a green mineral consisting of hydrated silicate of potassium or iron or magnesium or aluminum; found in greensand
- globin
- a colorless protein obtained by removing heme from hemoglobin; the oxygen carrying compound in red blood cells
- globular pearlite
- if steel or iron cool very slowly the cementite may occur in globules instead of in layers
- globulin
- a family of proteins found in blood and milk and muscle and in plant seed
- glop
- any gummy shapeless matter; usually unpleasant
- glove leather
- leather suitable for making gloves
- glucocorticoid
- a steroid hormone that is produced by the adrenal cortex of animals; affects functioning of gonads and has anti-inflammatory activity
- glucosamine
- an amino derivative of glucose that is a component of many polysaccharides
- glucose
- a monosaccharide sugar that has several forms; an important source of physiological energy
- glucoside
- a glycoside derived from glucose
- glue
- cement consisting of a sticky substance that is used as an adhesive
- glutamate
- a salt or ester of glutamic acid
- glutamic acid
- an amino acid occurring in proteins; important in the nitrogen metabolism of plants; used in monosodium glutamate to enhance the flavor of meats
- glutamic oxalacetic transaminase
- an enzyme involved in transamination
- glutamine
- a crystalline amino acid occurring in proteins; important in protein metabolism
- glutathione peroxidase
- an enzyme in the body that is a powerful scavenger of free radicals
- glutelin
- a simple protein found in the seeds of cereals
- glyceraldehyde
- a sweet crystalline aldehyde formed by the breakdown of sugars
- glyceric acid
- a syrupy acid obtained by oxidation of glycerol or glyceraldehyde
- glycerin jelly
- a mixture of glycerin and gelatin that is used in histology for mounting specimens
- glycerin
- a sweet syrupy trihydroxy alcohol obtained by saponification of fats and oils
- glycerinated gelatin
- a gelatinous preparation made from gelatin and glycerin and water; used as a base for ointments and suppositories
- glycerite
- a medicine made by mixing a substance in glycerin
- glycerogel
- a medicated skin preparation made from glycerin and glycerinated gelatin
- glycerol trimargarate
- a glyceryl ester of margaric acid
- glycerol tripalmitate
- a triglyceride of palmitic acid
- glycerol tristearate
- a triglyceride of stearic acid
- glyceryl
- a trivalent radical derived from glycerol by removing the three hydroxyl radicals
- glyceryl ester
- an ester of glycerol
- glycine
- the simplest amino acid found in proteins and the principal amino acid in sugar cane
- glycolic acid
- a translucent crystalline compound found in sugar cane and sugar beets and unripe grapes
- glycoprotein
- a conjugated protein having a carbohydrate component
- glycoside
- a group of compounds derived from monosaccharides
- glyoxaline
- an organic base C3H4N2; a histamine inhibitor
- gneiss
- a laminated metamorphic rock similar to granite
- goatskin
- the hide of a goat
- goethite
- a red or yellow or brown mineral; an oxide of iron that is a common constituent of rust
- goitrogen
- any substance (such as thiouracil) that induces the formation of a goiter
- gold dust
- the particles and flakes (and sometimes small nuggets) of gold obtained in placer mining
- Golden Fleece
- in Greek mythology, a fleece of gold owned by the king of Colchis and guarded in a sacred grove by a dragon; recovered by Jason and the Argonauts
- goldstone
- aventurine spangled densely with fine gold-colored particles
- goo
- any thick, viscous matter
- goose grease
- grease derived from geese
- grain
- the side of leather from which the hair has been removed
- Gram's solution
- a solution used in staining bacteria by Gram's method; consists of one part iodine and two parts potassium iodide and 300 parts water
- granite
- plutonic igneous rock having visibly crystalline texture; generally composed of feldspar and mica and quartz
- graph paper
- paper that has lines to permit drawing graphs
- graphic tellurium
- a silver-white mineral consisting of silver gold telluride; a source of gold in Australia and America
- grease
- a thick fatty oil (especially one used to lubricate machinery)
- greaseproof paper
- paper that is impermeable to oil or grease; used in cooking
- Greek fire
- a mixture used by Byzantine Greeks that was often shot at adversaries; catches fire when wetted
- green gold
- a gold alloy (at least 14 karat gold with silver or silver and cadmium) that has a green appearance
- green lead ore
- a mineral consisting of lead chloride and phosphate; a minor source of lead
- green manure
- a growing crop that is plowed under to enrich soil
- greenhouse emission
- a gas that contributes to the greenhouse effect by absorbing infrared radiation
- Greenland spar
- a white mineral consisting of fluorides of aluminum and sodium; a source of fluorine
- greensand
- an olive-green sandstone containing glauconite
- greisen
- a granitic rock composed of quartz and mica
- grid metal
- a kind of hard lead that is used for grids in storage batteries
- grit
- a hard coarse-grained siliceous sandstone
- ground glass
- glass that diffuses light due to a rough surface produced by abrasion or etching
- ground glass
- particulate glass made by grinding and used as an abrasive
- ground water
- underground water that is held in the soil and in pervious rocks
- groundmass
- (geology) the matrix of fine-grained crystalline material in which larger crystals are embedded
- grout
- a thin mortar that can be poured and used to fill cracks in masonry or brickwork
- growth factor
- a protein that is involved in cell differentiation and growth
- growth regulator
- (botany) a plant product that acts like a hormone
- grume
- a thick viscous liquid
- guano
- the excrement of sea birds; used as fertilizer
- guar gum
- a gum from seeds of the guar plant; used to thicken foods and as sizing for paper and cloth
- guinea gold
- 22-karat gold from which guinea coins were made
- guinea gold
- brass with enough copper to give it a reddish tint; used for plumbing pipe and other brass hardware and in cheap jewelry
- gum
- any of various substances (soluble in water) that exude from certain plants; they are gelatinous when moist but harden on drying
- gum acacia
- gum from an acacia tree; used as a thickener (especially in candies and pharmaceuticals)
- gum kino
- a gum obtained from various tropical plants; used as an astringent and in tanning
- gum labdanum
- a dark brown to greenish oleoresin that has a fragrant odor and is used as a fixative in perfumes; obtained as a juice from certain rockroses
- gum resin
- a mixture of resin and gum
- gum sangapenum
- a variety of gum
- gum terpentine
- obtained from conifers (especially pines)
- gum-lac
- an inferior lac produced by lac insects in Madagascar
- gumbo
- any of various fine-grained silty soils that become waxy and very sticky mud when saturated with water
- gummite
- a gummy orange mixture of uranium oxides and silicates occurring naturally in the hydration and oxidation of pitchblende
- gunite
- a mixture of cement and sand and water that is sprayed on a surface under pneumatic pressure
- gunmetal
- a type of bronze used for parts subject to wear or corrosion (especially corrosion by sea water)
- gunpowder
- a mixture of potassium nitrate, charcoal, and sulfur in a 75:15:10 ratio which is used in gunnery, time fuses, and fireworks
- gutta-percha
- a whitish rubber derived from the coagulated milky latex of gutta-percha trees; used for insulation of electrical cables
- gypsum
- a common white or colorless mineral (hydrated calcium sulphate) used to make cements and plasters (especially plaster of Paris)
- H
- a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
- H2O
- binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent
- haem
- a complex red organic pigment containing iron and other atoms to which oxygen binds
- haematite
- the principal form of iron ore; consists of ferric oxide in crystalline form; occurs in a red earthy form
- haemoprotein
- a conjugated protein linked to a compound of iron and porphyrin
- haemosiderin
- a granular brown substance composed of ferric oxide; left from the breakdown of hemoglobin; can be a sign of disturbed iron metabolism
- Hageman factor
- coagulation factor whose deficiency results in prolongation of clotting time of venous blood
- hailstone
- small pellet of ice that falls during a hailstorm
- hair coloring
- a dye for coloring the hair
- halibut-liver oil
- a fatty oil from halibut livers that is used as a source of vitamin A
- halide
- a salt of any halogen acid
- halite
- naturally occurring crystalline sodium chloride
- halitosis
- offensive breath
- halocarbon
- one of various compounds of carbon and any of the halogens
- haloform
- compounds with the formula CHX3, where X is a halogen atom
- halogen
- any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions
- halon
- a compound in which the hydrogen atoms of a hydrocarbon have been replaced by bromine and other halogen atoms; very stable; used in fire extinguishers although it is thought to release bromine that depletes the ozone layer
- hanging chad
- a chad that is incompletely removed and hanging by one corner
- haptoglobin
- a protein in plasma that binds free hemoglobin and removes it (as from wounds)
- hard lead
- unrefined lead that is hard because of the impurities it contains
- hard solder
- solder that contains copper; melts at a relatively high temperature; used for brazing
- hard steel
- steel with more than 0.3% carbon
- hard water
- water that contains mineral salts (as calcium and magnesium ions) that limit the formation of lather with soap
- hardtack
- a mountain mahogany
- hardwood
- the wood of broad-leaved dicotyledonous trees (as distinguished from the wood of conifers)
- harlequin opal
- a reddish opal with small patches of brilliant color
- hausmannite
- a mineral consisting of manganese tetroxide; a source of manganese
- HAZMAT
- an abbreviation for `hazardous material' used on warning signs
- Hb
- a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues
- HCFC
- a fluorocarbon that is replacing chlorofluorocarbon as a refrigerant and propellant in aerosol cans; considered to be somewhat less destructive to the atmosphere
- HCG
- hormone produced early in pregnancy by the placenta; detection in the urine and serum is the basis for one kind of pregnancy test
- HDL
- a lipoprotein that transports cholesterol in the blood; composed of a high proportion of protein and relatively little cholesterol; high levels are thought to be associated with decreased risk of coronary heart disease and atherosclerosis
- HDL cholesterol
- the cholesterol in high-density lipoproteins; the `good' cholesterol; a high level in the blood is thought to lower the risk of coronary artery disease
- He
- a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
- heavy metal
- a metal of relatively high density (specific gravity greater than about 5) or of high relative atomic weight (especially one that is poisonous like mercury or lead)
- helium group
- the series of inert gases
- hematochrome
- a reddish coloring material found in some algae
- hemiacetal
- an organic compound usually formed as an intermediate product in the preparation of acetals from aldehydes or ketones
- hemin
- a reddish-brown chloride of heme; produced from hemoglobin in laboratory tests for the presence of blood
- hemlock
- poisonous drug derived from an Eurasian plant of the genus Conium
- hemp
- a plant fiber
- henna
- a reddish brown dye used especially on hair
- hepatotoxin
- any toxin that affects the liver
- heptadecanoic acid
- a colorless crystalline synthetic fatty acid
- heptane
- a colorless volatile highly flammable liquid obtained from petroleum and used as an anesthetic or a solvent or in determining octane ratings
- herbicide
- a chemical agent that destroys plants or inhibits their growth
- heterocycle
- a compound containing a heterocyclic ring
- heulandite
- a group of minerals of the zeolite family consisting of a hydrous aluminum silicate of sodium and calcium
- hexadecanoic acid
- a saturated fatty acid that is the major fat in meat and dairy products
- hexane
- a colorless flammable liquid alkane derived from petroleum and used as a solvent
- hexestrol
- estrogen compound used to treat menstrual irregularities and menopausal symptoms and to prevent pregnancy
- hexose
- a monosaccharide that contains six carbon atoms per molecule
- Hf
- a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons
- HFC
- a fluorocarbon emitted as a by-product of industrial manufacturing
- Hg
- a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures
- hiddenite
- a green transparent form of the mineral spodumene used as a gemstone
- high brass
- brass with 35% zinc
- high explosive
- a powerful chemical explosive that produces gas at a very high rate
- high-level radioactive waste
- radioactive waste that left in a nuclear reactor after the nuclear fuel has been consumed
- high-speed steel
- an alloy steel that remains hard at a red heat; used to make metal-cutting tools
- high-strength brass
- a brass with from 1-4% manganese to harden it
- hip tile
- a tile shaped so as to cover the hip of a hip roof
- histaminase
- enzyme that acts as a catalyst in converting histidine to histamine
- histidine
- an essential amino acid found in proteins that is important for the growth and repair of tissue
- histone
- a simple protein containing mainly basic amino acids; present in cell nuclei in association with nucleic acids
- HN
- a colorless explosive liquid that is volatile and poisonous and foul-smelling
- Ho
- a trivalent metallic element of the rare earth group; occurs together with yttrium; forms highly magnetic compounds
- holy water
- water that has been blessed by a priest for use in symbolic purification
- homogenate
- material that has been homogenized (especially tissue that has been ground and mixed)
- Hooker's green
- green pigment consisting of Prussian blue mixed with gamboge
- horn
- the material (mostly keratin) that covers the horns of ungulates and forms hooves and claws and nails
- hornblende
- a green to black mineral of the amphibole group; consists of silicates of calcium and sodium and magnesium and iron
- hornfels
- a fine-grained metamorphic rock formed by the action of heat on clay rocks
- horse manure
- horse excreta used as fertilizer
- horsehair
- hair taken from the mane or tail of a horse
- horsehide
- leather from the hide of a horse
- horseradish peroxidase
- an enzyme used in immunohistochemistry to label antigens and their antibodies
- hot air
- air that has been heated and tends to rise
- Hs
- a radioactive transuranic element
- hudson seal
- muskrat fur dressed to simulate sealskin
- human waste
- the body wastes of human beings
- humate
- material that is high in humic acids
- humectant
- any substance that is added to another substance to keep it moist
- humic acid
- a dark brown humic substance that is soluble in water only at pH values greater than 2
- humic shale
- shale that is rich in humic acids
- humic substance
- an organic residue of decaying organic matter
- humin
- a black humic substance that is not soluble in water
- humus
- partially decomposed organic matter; the organic component of soil
- hyacinth
- a red transparent variety of zircon used as a gemstone
- hyalin
- a glassy translucent substance that occurs in hyaline cartilage or in certain skin conditions
- hyaluronic acid
- a viscous mucopolysaccharide found in the connective tissue space and the synovial fluid of movable joints and the humors of the eye; a cementing and protective substance
- Hyazyme
- an enzyme (trade name Hyazyme) that splits hyaluronic acid and so lowers its viscosity and increases the permeability of connective tissue and the absorption of fluids
- hydrate
- any compound that contains water of crystallization
- hydrated oxide
- a compound of an oxide with water
- hydrazine
- a colorless fuming corrosive liquid; a powerful reducing agent; used chiefly in rocket fuels
- hydrazo group
- the bivalent group -HNNH- derived from hydrazine
- hydrazoite
- a salt of hydrazoic acid
- hydride
- any binary compound formed by the union of hydrogen and other elements
- hydriodic acid
- (HI) a colorless or yellow aqueous solution of hydrogen iodide
- hydrobromic acid
- an aqueous solution of hydrogen bromide that is a strong liquid acid
- hydrocarbon
- an organic compound containing only carbon and hydrogen
- hydrochloride
- a complex consisting of an organic base in association with hydrogen chloride
- hydrocolloid
- a substance that forms a gel with water
- Hydrocortone
- an adrenal-cortex hormone (trade names Hydrocortone or Cortef) that is active in carbohydrate and protein metabolism
- hydrocyanic acid
- a solution of hydrogen cyanide in water; weak solutions are used in fumigating and in the synthesis of organic compounds
- hydrofluoric acid
- a weak poisonous liquid acid; formed by solution of hydrogen fluoride in water
- hydrogel
- a colloidal gel in which water is the dispersion medium
- hydrogen atom
- an atom of hydrogen
- hydrogen bromide
- a colorless gas that yields hydrobromic acid in solution with water
- hydrogen chloride
- a colorless corrosive gas (HCl)
- hydrogen cyanide
- a highly poisonous gas or volatile liquid that smells like bitter almonds; becomes a gas at around 90 degree Fahrenheit and is most dangerous when inhaled; the anhydride of hydrocyanic acid; used in manufacturing
- hydrogen fluoride
- a colorless poisonous corrosive liquid made by the action of sulphuric acid on calcium fluoride; solutions in water are hydrofluoric acid
- hydrogen iodide
- a colorless gas that yields hydroiodic acid in aqueous solution
- hydrogen peroxide
- a viscous liquid with strong oxidizing properties; a powerful bleaching agent; also used (in aqueous solutions) as a mild disinfectant and (in strong concentrations) as an oxidant in rocket fuels
- hydrogen sulfide
- a sulfide having the unpleasant smell of rotten eggs
- hydroiodic acid
- an acid formed by aqueous solution of hydrogen iodide
- hydrolysate
- a product of hydrolysis
- hydroxide
- a chemical compound containing the hydroxyl group
- hydroxide ion
- the anion OH having one oxygen and one hydrogen atom
- hydroxy acid
- any acid that has hydroxyl groups in addition to the hydroxyl group in the acid itself
- hydroxybenzoic acid
- a crystalline derivative of benzoic acid
- hydroxybutyric acid
- hydroxy derivative of butyric acid
- hydroxyl
- the monovalent group -OH in such compounds as bases and some acids and alcohols
- hydroxymethyl
- a methyl with hydroxide replacing the hydrogen atoms
- hydroxyproline
- a crystalline amino acid obtained from gelatin or collagen
- hyper-eutectoid steel
- a steel that contains more than 0.9% carbon
- hypnagogue
- an agent that induces drowsiness or sleep
- hypo
- a compound used as a fixing agent in photographic developing
- hypo-eutectoid steel
- a steel that contains less that 0.9% carbon
- hypochlorite
- any salt or ester of hypochlorous acid
- hypochlorous acid
- a weak unstable acid known only in solution and in its salts; used as a bleaching agent and as an oxidizing agent
- hypoglycaemic agent
- any of various agents that decrease the level of glucose in the blood and are used in the treatment of diabetes mellitus
- hyponitrous acid
- an explosive white crystalline weak acid (H2N2O2)
- hypophosphoric acid
- a crystalline tetrabasic acid (H4P2O6)
- hypophosphorous acid
- a clear or yellow monobasic acid (H3PO2)
- I
- a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks)
- IAA
- a plant hormone promoting elongation of stems and roots
- ice
- water frozen in the solid state
- Iceland spar
- a transparent calcite found in Iceland and used in polarizing microscopes
- ichor
- (Greek mythology) the rarified fluid said to flow in the veins of the Gods
- icicle
- ice resembling a pendent spear, formed by the freezing of dripping water
- ICSH
- a gonadotropic hormone that is secreted by the anterior pituitary; stimulates ovulation in female mammals and stimulates androgen release in male mammals
- ideal gas
- a hypothetical gas with molecules of negligible size that exert no intermolecular forces
- identification particle
- a tiny particle of material that can be added to a product to indicate the source of manufacture
- idocrase
- a green or yellow or brown mineral consisting of a hydrated silicate; it occurs as crystals in limestone and is used a gemstone
- Ig
- a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response
- igneous rock
- rock formed by the solidification of molten magma
- igniter
- a substance used to ignite or kindle a fire
- illuminant
- something that can serve as a source of light
- ilmenite
- a weakly magnetic black mineral found in metamorphic and plutonic rocks; an iron titanium oxide in crystalline form; a source of titanium
- imide
- any of a class of organic compounds that contain the divalent radical -CONHCO-
- immunoglobulin A
- one of the most common of the five major classes of immunoglobulins; the chief antibody in the membranes of the gastrointestinal and respiratory tracts
- immunoglobulin D
- one of the five major classes of immunoglobulins; present in blood serum in small amounts
- immunoglobulin E
- one of the five major classes of immunoglobulins; present primarily in the skin and mucous membranes
- immunoglobulin G
- one of the five major classes of immunoglobulins; the main antibody defense against bacteria
- immunoglobulin M
- one of the five major classes of immunoglobulins; involved in fighting blood infections and in triggering production of immunoglobulin G
- impregnation
- material with which something is impregnated
- In
- a rare soft silvery metallic element; occurs in small quantities in sphalerite
- incense
- a substance that produces a fragrant odor when burned
- Inconel
- a nickel-base alloy with chromium and iron; used in gas-turbine blades
- indelible ink
- ink that cannot be erased or washed away
- indene
- a colorless liquid hydrocarbon extracted from petroleum or coal tar and used in making synthetic resins
- India ink
- a black liquid ink used for printing or writing or drawing
- india paper
- a thin tough opaque paper used in fine books
- India rubber
- an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products
- Indian red
- a red soil containing ferric oxide; often used as a pigment
- Indian red
- a red pigment composed in part from ferric oxide which is often used in paints and cosmetics
- indicator
- (chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction
- indolebutyric acid
- a synthetic plant hormone promoting elongation of stems and roots
- inducer
- an agent capable of activating specific genes
- indurated clay
- hardened clay
- informational RNA
- the template for protein synthesis; the form of RNA that carries information from DNA in the nucleus to the ribosome sites of protein synthesis in the cell
- ingot iron
- iron of high purity
- inhalant
- something that is inhaled
- inhibitor
- a substance that retards or stops an activity
- injectant
- any solution that is injected (as into the skin)
- ink
- a liquid used for printing or writing or drawing
- inoculant
- a substance (a virus or toxin or immune serum) that is introduced into the body to produce or increase immunity to a particular disease
- inorganic compound
- any compound that does not contain carbon
- inorganic phosphate
- a salt of phosphoric acid
- inosine
- a nucleoside that is formed by the deamination of adenosine; used in kidney transplantation to provide a temporary source of sugar
- inositol
- an optically inactive alcohol that is a component of the vitamin B complex
- insect powder
- a chemical used to kill insects
- insect repellant
- a chemical substance that repels insects
- instillation
- a liquid that is instilled drop by drop
- insulant
- insulating material that reduces or prevents the transmission of heat or sound or electricity
- interleukin
- any of several lymphokines that promote macrophages and killer T cells and B cells and other components of the immune system
- intermediate
- a substance formed during a chemical process before the desired product is obtained
- intrinsic factor
- a substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12
- Intropin
- a monoamine neurotransmitter found in the brain and essential for the normal functioning of the central nervous system; as a drug (trade names Dopastat and Intropin) it is used to treat shock and hypotension
- inulin
- used to manufacture fructose and in assessing kidney function
- Invar
- an alloy of iron and nickel having a low coefficient of thermal expansion; used in tuning forks and measuring tapes and other instruments
- invert sugar
- a mixture of equal parts of glucose and fructose resulting from the hydrolysis of sucrose; found naturally in fruits; sweeter than glucose
- invertase
- an enzyme that catalyzes the hydrolysis of sucrose into glucose and fructose
- iodic acid
- a soluble crystalline acid; used as a reagent and disinfectant
- iodide
- a salt or ester of hydriodic acid
- iodinated protein
- a protein that contains iodine
- iodine-125
- light radioactive isotope of iodine with a half-life of 60 days; used as a tracer in thyroid studies and as a treatment for hyperthyroidism
- iodine-131
- heavy radioactive isotope of iodine with a half-life of 8 days; used in a sodium salt to diagnose thyroid disease and to treat goiter
- iodoamino acid
- an amino acid with iodine added
- iodocompound
- a compound containing the covalent iodine radical
- iodoform
- sweet smelling yellow solid haloform CHI3
- iodopsin
- a violet photopigment in the retinal cones of the eyes of most vertebrates; plays a role in daylight vision
- iodothyronine
- thyronine with iodine added
- iodotyrosine
- tyrosine with iodine added
- Ir
- a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium
- iridosmine
- a hard and corrosion resistant mineral that is a natural alloy of osmium and iridium (usually containing small amounts of rhodium and platinum); used in needles and pen nibs etc.
- iron disulfide
- a compound containing two atoms of sulfur combined with iron
- iron manganese tungsten
- a mineral consisting of iron and manganese tungstate in crystalline form; the principal ore of tungsten; found in quartz veins associated with granitic rocks
- iron ore
- an ore from which iron can be extracted
- iron perchloride
- a highly toxic chemical used to engrave metal plates and electronic circuits
- iron putty
- a cement resembling putty; made by mixing ferric oxide and boiled linseed oil; is acid resistant
- isinglass
- any of various minerals consisting of hydrous silicates of aluminum or potassium etc. that crystallize in forms that allow perfect cleavage into very thin leaves; used as dielectrics because of their resistance to electricity
- isoagglutinin
- an antibody produced by one individual that causes agglutination of red blood cells in other individuals of the same species
- isoagglutinogen
- an antigen capable of causing the production of (or reacting with) an isoagglutinin
- isobutylene
- used also in making gasoline components
- isocyanate
- a salt or ester of isocyanic acid
- isocyanic acid
- an acid known only in the form of its esters
- isoleucine
- an essential amino acid found in proteins; isomeric with leucine
- isomer
- a compound that exists in forms having different arrangements of atoms but the same molecular weight
- isomerase
- an enzyme that catalyzes its substrate to an isomeric form
- isopropanol
- alcohol used as antifreeze or a solvent
- isosmotic solution
- a solution having the same osmotic pressure as blood
- isothiocyanate
- a family of compounds derived from horseradish and radishes and onions and mustards; source of the hotness of those plants and preparations
- isotope
- one of two or more atoms with the same atomic number but with different numbers of neutrons
- itaconic acid
- a crystalline carboxylic acid; occurs in some fermentations of sugars
- ivory black
- a black pigment made from grinding burnt ivory in oil
- ivory
- a hard smooth ivory colored dentine that makes up most of the tusks of elephants and walruses
- jade
- a semiprecious gemstone that takes a high polish; is usually green but sometimes whitish; consists of jadeite or nephrite
- jadeite
- a hard green mineral consisting of sodium aluminum silicate in monoclinic crystalline form; a source of jade; found principally in Burma
- jaggary
- unrefined brown sugar made from palm sap
- Japan tallow
- a yellow wax obtained from sumac berries; used in polishes
- jargon
- a colorless (or pale yellow or smoky) variety of zircon
- jasper
- an opaque form of quartz; red or yellow or brown or dark green in color; used for ornamentation or as a gemstone
- jelly
- any substance having the consistency of jelly or gelatin
- jet
- a hard black form of lignite that takes a brilliant polish and is used in jewelry or ornamentation
- joss stick
- a slender stick of incense burned before a joss by the Chinese
- jumping gene
- a segment of DNA that can become integrated at many different sites along a chromosome (especially a segment of bacterial DNA that can be translocated as a whole)
- juniperic acid
- a crystalline acid found in the exudations of some conifers
- junk DNA
- stretches of DNA that do not code for genes
- jute
- a plant fiber used in making rope or sacks
- K
- a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
- K-Dur 20
- salt of potassium (KCl) (trade names K-Dur 20, Kaochlor and K-lor and Klorvess and K-lyte); taken in tablet form to treat potassium deficiency
- kainite
- a white mineral consisting of magnesium sulphate and potassium chloride; a source of potassium salts; used as a fertilizer
- kaolinite
- a mineral consisting of aluminum silicate; main source of kaolin
- kapok
- a plant fiber from the kapok tree; used for stuffing and insulation
- karaya gum
- exudate of an Asian tree; used for finishing textiles and to thicken foodstuffs and cosmetics
- kauri
- resin of the kauri trees of New Zealand; found usually as a fossil; also collected for making varnishes and linoleum
- Kekule formula
- a closed chain of 6 carbon atoms with hydrogen atoms attached
- Kendal green
- a green dye, often used to color cloth, which is obtained from the woad plant
- keratohyalin
- hyaline in the large granules of the stratum granulosum
- kernite
- a light soft mineral consisting of hydrated sodium borate in crystalline form; an important source of boron
- ketohexose
- a monosaccharide having six carbon atoms and a ketone group
- ketone
- any of a class of organic compounds having a carbonyl group linked to a carbon atom in each of two hydrocarbon radicals
- ketone group
- a group having the characteristic properties of ketones
- ketose
- any monosaccharide sugar that contains a ketone group or its hemiacetal
- ketosteroid
- a steroid containing a ketone group
- kid
- soft smooth leather from the hide of a young goat
- kieserite
- a white mineral consisting of hydrous magnesium sulfate often found in salt mines
- kimberlite
- a rare type of peridotite that sometimes contains diamonds; found in South Africa and Siberia
- kinase
- an enzyme that catalyzes the conversion of a proenzyme to an active enzyme
- kindling
- material for starting a fire
- Kitty Litter
- granulated clay; placed in a container where it absorbs the waste products of a cat or dog
- Kleenex
- a piece of soft absorbent paper (usually two or more thin layers) used as a disposable handkerchief
- knot
- a hard cross-grained round piece of wood in a board where a branch emerged
- knothole
- a hole in a board where a knot came out
- kokoi venom
- a potent neurotoxin found in a particular frog
- Kr
- a colorless element that is one of the six inert gasses; occurs in trace amounts in air
- kraft
- strong wrapping paper made from pulp processed with a sulfur solution
- kunzite
- a pinkish lilac crystal form of the mineral spodumene that is used as a gemstone
- Kwell
- a preparation of lindane (trade name Kwell) that is used to kill lice and itch mites; available in cream or shampoo
- La
- a white soft metallic element that tarnishes readily; occurs in rare earth minerals and is usually classified as a rare earth
- label
- a radioactive isotope that is used in a compound in order to trace the mechanism of a chemical reaction
- lac
- resinlike substance secreted by certain lac insects; used in e.g. varnishes and sealing wax
- lac dye
- scarlet dye like cochineal; extracted with alkali from stick lac
- lac wax
- a hard wax separated from shellac by its insolubility in alcohol
- lachrymator
- a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds
- lacquer
- a black resinous substance obtained from certain trees and used as a natural varnish
- Lactaid
- any of a group of enzymes (trade name Lactaid) that hydrolyze lactose to glucose and galactose
- lactalbumin
- albumin occurring in milk
- lactate
- a salt or ester of lactic acid
- lactic acid
- a clear odorless hygroscopic syrupy carboxylic acid found in sour milk and in many fruits
- lactifuge
- any agent that reduces milk secretion (as given to a woman who is not breast feeding)
- lactogen
- any agent that enhances milk production
- lactogenic hormone
- gonadotropic hormone secreted by the anterior pituitary; in females it stimulates growth of the mammary glands and lactation after parturition
- lactose
- a sugar comprising one glucose molecule linked to a galactose molecule; occurs only in milk
- laetrile
- a substance derived from amygdalin; publicized as an antineoplastic drug although there is no supporting evidence
- lagging
- insulation used to wrap around pipes or boilers or laid in attics to prevent loss of heat
- laid paper
- writing paper having a watermark of fine lines running across the grain
- lake
- any of numerous bright translucent organic pigments
- lake
- a purplish red pigment prepared from lac or cochineal
- lambskin
- the skin of a lamb with the wool still on
- lambskin
- skin of a sheep or goat prepared for writing on
- lamellar mixture
- a mixture in which substances occur in distinct layers
- laminated glass
- glass made with plates of plastic or resin or other material between two sheets of glass to prevent shattering
- langbeinite
- a mineral consisting of potassium magnesium double sulphate; used as a fertilizer
- lanolin
- a yellow viscous animal oil extracted from wool; a mixture of fatty acids and esters; used in some ointments and cosmetics
- lanthanide series
- the rare-earth elements with atomic numbers 57 through 71; having properties similar to lanthanum
- lanthanide
- any element of the lanthanide series (atomic numbers 57 through 71)
- lapin
- the fur of a rabbit
- lapis lazuli
- an azure blue semiprecious stone
- lard oil
- oil consisting chiefly of olein that is expressed from lard and used especially as a lubricant, cutting oil or illuminant
- larvacide
- an insecticide that kills the larvae of insects
- larvicide
- a chemical used to kill larval pests
- latakia
- aromatic Turkish tobacco
- laterite
- a red soil produced by rock decay; contains insoluble deposits of ferric and aluminum oxides
- latex
- a milky exudate from certain plants that coagulates on exposure to air
- lath and plaster
- a building material consisting of thin strips of wood that provide a foundation for a coat of plaster
- latten
- brass (or a yellow alloy resembling brass) that was hammered into thin sheets; formerly used for church utensils
- lava
- rock that in its molten form (as magma) issues from volcanos; lava is what magma is called when it reaches the surface
- LDL
- a lipoprotein that transports cholesterol in the blood; composed of moderate amount of protein and a large amount of cholesterol; high levels are thought to be associated with increased risk of coronary heart disease and atherosclerosis
- LDL cholesterol
- the cholesterol in low-density lipoproteins; the `bad' cholesterol; a high level in the blood is thought to be related to various pathogenic conditions
- lead acetate
- a poisonous white solid (Pb[CH3CO]2) used in dyeing cotton and in making enamels and varnishes
- lead arsenate
- a poisonous white solid (Pb3[AsO4]2) used as an insecticide
- lead chromate
- a poisonous chromate of lead used as a pigment in paint
- lead glass
- glass containing lead oxide; has a high refractive index
- lead ore
- ore containing lead
- lead tetraethyl
- a clear oily poisonous liquid added to gasoline to prevent knocking
- leaded bronze
- bronze to which 1-4% lead is added
- leaded gasoline
- gasoline treated with a lead compound to reduce motor knocks
- leaf fat
- fat lining the abdomen and kidneys in hogs which is used to make lard
- leaf mold
- soil composed mainly of decaying leaves
- leather
- an animal skin made smooth and flexible by removing the hair and then tanning
- leaven
- a substance used to produce fermentation in dough or a liquid
- lecithin
- a yellow phospholipid essential for the metabolism of fats; found in egg yolk and in many plant and animal cells; used commercially as an emulsifier
- lectin
- any of several plant glycoproteins that act like specific antibodies but are not antibodies in that they are not evoked by an antigenic stimulus
- ledger paper
- a durable writing paper used in record books and business ledgers
- lemon grass
- an aromatic oil that smells like lemon and is widely used in Asian cooking and in perfumes and medicines
- leopard
- the pelt of a leopard
- lepidocrocite
- a red to reddish brown mineral consisting of iron oxide hydroxide; often found in iron ores together with goethite
- lepidolite
- a mineral of the mica group; an important source of lithium
- lepidomelane
- a mica that is a biotite containing iron
- letter paper
- writing paper for use in writing correspondence
- leucine
- a white crystalline amino acid occurring in proteins that is essential for nutrition; obtained by the hydrolysis of most dietary proteins
- Levant morocco
- a heavy morocco often used in bookbinding
- Li
- a soft silver-white univalent element of the alkali metal group; the lightest metal known; occurs in several minerals
- library paste
- an adhesive made from water and flour or starch; used on paper and paperboard
- ligand
- a substance (an atom or molecule or radical or ion) that forms a complex around a central atom
- lignin
- a complex polymer; the chief constituent of wood other than carbohydrates; binds to cellulose fibers to harden and strengthen cell walls of plants
- limestone
- a sedimentary rock consisting mainly of calcium that was deposited by the remains of marine animals
- limewater
- solution of calcium hydroxide in water used as an antacid
- limonene
- a liquid terpene with a lemon odor; found in lemons and oranges and other essential oils
- limonite
- a widely occurring iron oxide ore; a mixture of goethite and hematite and lepidocrocite
- linalool
- a colorless fragrant liquid found in many essential oils
- lindane
- a white crystalline powder used as an agricultural insecticide
- linen
- a high-quality paper made of linen fibers or with a linen finish
- lino
- a floor covering
- linoleic acid
- a liquid polyunsaturated fatty acid abundant in plant fats and oils; a fatty acid essential for nutrition; used to make soap
- linolenic acid
- a liquid polyunsaturated fatty acid that occurs in some plant oils; an essential fatty acid
- lint
- fine ravellings of cotton or linen fibers
- linuron
- a herbicide that kills weeds without harming vegetables
- lipase
- an enzyme secreted in the digestive tract that catalyzes the breakdown of fats into individual fatty acids that can be absorbed into the bloodstream
- lipid
- an oily organic compound insoluble in water but soluble in organic solvents; essential structural component of living cells (along with proteins and carbohydrates)
- Lipo-Lutin
- a steroid hormone (trade name Lipo-Lutin) produced in the ovary; prepares and maintains the uterus for pregnancy
- lipoprotein
- a conjugated protein having a lipid component; the principal means for transporting lipids in the blood
- liquid
- fluid matter having no fixed shape but a fixed volume
- liquid
- a substance that is liquid at room temperature and pressure
- liquid air
- air in a liquid state
- liquid bleach
- a solution containing bleaching agents; used for laundry
- liquid crystal
- a liquid exhibiting properties of a crystal that are not shown by ordinary liquids
- liquid nitrogen
- nitrogen in a liquid state
- Liquid Pred
- a dehydrogenated analogue of cortisol (trade names Orasone or Deltasone or Liquid Pred or Meticorten); used as an anti-inflammatory drug in the treatment of arthritis and as an immunosuppressant
- liquor
- a liquid substance that is a solution (or emulsion or suspension) used or obtained in an industrial process
- lithia water
- mineral water containing lithium salts
- Lithonate
- a white powder (LiCO3) used in manufacturing glass and ceramics and as a drug; the drug (trade names Lithane or Lithonate or Eskalith) is used to treat some forms of depression and manic episodes of manic-depressive disorder
- litmus paper
- unsized paper treated with litmus for use as an acid-base indicator
- litmus
- a coloring material (obtained from lichens) that turns red in acid solutions and blue in alkaline solutions; used as a very rough acid-base indicator
- litter
- rubbish carelessly dropped or left about (especially in public places)
- live steam
- steam coming from a boiler at full pressure
- loadstone
- a permanent magnet consisting of magnetite that possess polarity and has the power to attract as well as to be attracted magnetically
- loam
- a rich soil consisting of a mixture of sand and clay and decaying organic materials
- loess
- a fine-grained unstratified accumulation of clay and silt deposited by the wind
- log
- a segment of the trunk of a tree when stripped of branches
- long-staple cotton
- cotton with relatively long fibers
- low brass
- brass with 30% (or less) zinc
- low explosive
- an explosive with a low rate of combustion
- low-carbon steel
- steel with less than 0.15% carbon
- low-level radioactive waste
- (medicine) radioactive waste consisting of objects that have been briefly exposed to radioactivity (as in certain medical tests)
- LOX
- a bluish translucent magnetic liquid obtained by compressing gaseous oxygen and then cooling it below its boiling point; used as an oxidizer in rocket propellants
- Lr
- a radioactive transuranic element synthesized from californium
- Lu
- a trivalent metallic element of the rare earth group; usually occurs in association with yttrium
- lube
- a substance capable of reducing friction by making surfaces smooth or slippery
- luciferin
- pigment occurring in luminescent organisms (as fireflies); emits heatless light when undergoing oxidation
- lumber
- the wood of trees cut and prepared for use as building material
- lunar caustic
- silver nitrate fused into sticks and formerly used as a caustic
- lute
- a substance for packing a joint or coating a porous surface to make it impervious to gas or liquid
- lutein
- yellow carotenoid pigments in plants and animal fats and egg yolks
- lycopene
- carotenoid that makes tomatoes red; may lower the risk of prostate cancer
- lye
- a strong solution of sodium or potassium hydroxide
- lymphokine
- a cytokine secreted by helper T cells in response to stimulation by antigens and that acts on other cells of the immune system (as by activating macrophages)
- lysergic acid
- a crystalline acid often used in medical research; obtained from ergotic alkaloids
- lysin
- any substance (such as an antibody) or agent that can cause lysis
- lysine
- an essential amino acid found in proteins; occurs especially in gelatin and casein
- Lysol
- a clear oily brown solution of cresols in soap; used as an antiseptic and disinfectant
- lysozyme
- an enzyme found in saliva and sweat and tears that destroys the cell walls of certain bacteria
- Maalox
- an antacid
- macadam
- broken stone used in macadamized roadways
- macromolecule
- any very large complex molecule; found only in plants and animals
- magilp
- a medium for oil-paints; linseed oil mixed with mastic varnish or turpentine
- magma
- molten rock in the earth's crust
- magnesia
- a white solid mineral that occurs naturally as periclase; a source of magnesium
- magnesite
- a white mineral consisting of magnesium carbonate; a source of magnesium
- magnesium bicarbonate
- a bicarbonate that is a major cause of hard water
- magnesium carbonate
- a very white crystalline salt that occurs naturally as magnesite or as dolomite
- magnesium hydroxide
- a white crystalline powder used chiefly in medicines
- magnesium nitride
- a nitride containing nitrogen and magnesium
- magnesium sulfate
- a salt of magnesium
- magnetic ink
- an ink that contains particles of a magnetic substance whose presence can be detected by magnetic sensors
- magnetic iron-ore
- an oxide of iron that is strongly attracted by magnets
- magnetic pyrites
- a brownish iron sulfide mineral (FeS) having weak magnetic properties
- malachite
- a green or blue mineral used as an ore of copper and for making ornamental objects
- Malathion
- a yellow insecticide used as a dust or spray to control garden pests and house flies and mites
- maleate
- a salt or ester of maleic acid; used as a nontricyclic antidepressant drug for psychomotor activation
- maleic acid
- a colorless crystalline compound found in unripe fruit (such as apples or tomatoes or cherries) and used mainly to make polyester resins
- malt sugar
- a white crystalline sugar formed during the digestion of starches
- maltha
- a thick black tar intermediate between petroleum and asphalt
- man-made fiber
- fiber created from natural materials or by chemical processes
- manganate
- a salt of manganic acid containing manganese as its anion
- manganese tetroxide
- an oxide of manganese found naturally as hausmannite
- manganic acid
- a dibasic acid (H2MnO4) found only in solution and in manganate salts
- manganite
- a black mineral consisting of basic manganese oxide; a source of manganese
- manifold
- a lightweight paper used with carbon paper to make multiple copies
- manila
- a strong paper or thin cardboard with a smooth light brown finish made from e.g. Manila hemp
- Manilla hemp
- a kind of hemp obtained from the abaca plant in the Philippines
- manure
- any animal or plant material used to fertilize land especially animal excreta usually with litter material
- MAO
- an enzyme that catalyzes the oxidation of many body compounds (e.g., epinephrine and norepinephrine and serotonin)
- maple sugar
- sugar made from the sap of the sugar maple tree
- marble
- a hard crystalline metamorphic rock that takes a high polish; used for sculpture and as building material
- marine glue
- glue that is not water soluble
- marking ink
- an indelible ink for marking clothes or linens etc.
- marl
- a loose and crumbling earthy deposit consisting mainly of calcite or dolomite; used as a fertilizer for soils deficient in lime
- marlite
- metamorphic rock with approximately the same composition as marl
- marsh gas
- methane gas produced when vegetation decomposes in water
- martensite
- a solid solution of carbon in alpha-iron that is formed when steel is cooled so rapidly that the change from austenite to pearlite is suppressed; responsible for the hardness of quenched steel
- mash
- a mixture of mashed malt grains and hot water; used in brewing
- massicot
- the mineral form of lead monoxide; in the form of yellow powder it is used as a pigment
- mastic
- an aromatic exudate from the mastic tree; used chiefly in varnishes
- mastic
- a pasty cement used as an adhesive or filler
- matchwood
- wood suitable for making matchsticks
- matchwood
- wood in small pieces or splinters
- material
- the tangible substance that goes into the makeup of a physical object
- matrix
- (geology) a mass of fine-grained rock in which fossils, crystals, or gems are embedded
- matte
- a mixture of sulfides that forms when sulfide metal ores are smelted
- mechanical mixture
- a mixture whose components can be separated by mechanical means
- meconium
- thick dark green mucoid material that is the first feces of a newborn child
- medium
- a liquid with which pigment is mixed by a painter
- medium
- an intervening substance through which something is achieved
- medium
- (biology) a substance in which specimens are preserved or displayed
- medium steel
- steel with 0.15-0.3% carbon
- medulla
- a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers
- meerschaum
- a white clayey mineral
- megestrol
- a synthetic progestational compound used to treat endometrial carcinoma
- melaena
- abnormally dark tarry feces containing blood (usually from gastrointestinal bleeding)
- melamine resin
- a thermosetting resin formed from melamine and an aldehyde; used in molded products, adhesives, and coatings
- melanin
- insoluble pigments that account for the color of e.g. skin and scales and feathers
- meltwater
- melted snow or ice
- menhaden oil
- a fatty oil obtained from the menhaden fish and used in paint and ink and in treating leather
- menstruum
- (archaic) a solvent
- menthol
- a crystalline compound that has the cool and minty taste and odor that occurs naturally in peppermint oil; used as a flavoring and in medicine to relieve itching, pain, and nasal congestion
- mephitis
- a poisonous or foul smelling gas emitted from the earth
- mesquite gum
- a gum obtained from mesquite pods; resembles gum arabic
- message pad
- a pad of paper on which messages can be written
- mestranol
- a synthetic form of estrogen used in combination with a progestin in oral contraceptives
- metabolite
- any substance involved in metabolism (either as a product of metabolism or as necessary for metabolism)
- metal
- any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.
- metallized dye
- acid dye in which the negative ion contains a chelated metal atom
- metamorphic rock
- rock altered by pressure and heat
- metaphosphoric acid
- a glassy solid acid ([HPO3]n) often used as a dehydrating agent
- methane
- a colorless odorless gas used as a fuel
- methanol
- a light volatile flammable poisonous liquid alcohol; used as an antifreeze and solvent and fuel and as a denaturant for ethyl alcohol
- methionine
- a crystalline amino acid containing sulfur; found in most proteins and essential for nutrition
- methyl bromide
- a poisonous gas or liquid (CH3Br) used to fumigate rodents, worms, etc.
- methyl orange
- an azo dye used as an acid-base indicator; used for titrations involving weak bases
- methyl
- the univalent radical CH3- derived from methane
- methylated spirit
- ethyl alcohol denatured with methyl alcohol to prevent its use as an alcoholic beverage
- methylbenzene
- a colorless flammable liquid obtained from petroleum or coal tar; used as a solvent for gums and lacquers and in high-octane fuels
- methylene blue
- a dark green dye used as a stain, an antiseptic, a chemical indicator, and an antidote in cyanide poisoning
- methylene
- the bivalent radical CH2 derived from methane
- methyltestosterone
- an androgenic compound contained in drugs that are used to treat testosterone deficiency and female breast cancer and to stimulate growth and weight gain
- Mexican onyx
- a hard compact kind of calcite
- Mg
- a light silver-white ductile bivalent metallic element; in pure form it burns with brilliant white flame; occurs naturally only in combination (as in magnesite and dolomite and carnallite and spinel and olivine)
- microcosmic salt
- a white salt present in urine and used to test for metal oxides
- micronutrient
- a substance needed only in small amounts for normal body function (e.g., vitamins or minerals)
- Microtaggant
- (trademark) a microscopic and traceable identification particle used to trace explosives or other hazardous materials or to prevent counterfeiting
- milk glass
- a milky white translucent or opaque glass
- milk whey
- the serum or watery part of milk that is separated from the curd in making cheese
- millboard
- stout pasteboard used to bind books
- millerite
- a yellow mineral consisting of nickel sulfide; a minor source of nickel
- mine pig
- pig iron made entirely from ore
- mineral
- solid homogeneous inorganic substances occurring in nature having a definite chemical composition
- mineral jelly
- a semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication
- mineral oil
- a distillate of petroleum (especially one used medicinally as a laxative or stool softener)
- mineral wool
- a light fibrous material used as an insulator
- mineralocorticoid
- hormone that is one of the steroids of the adrenal cortex that influences the metabolism of sodium and potassium
- minium
- a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics
- mink
- the expensive fur of a mink
- mire
- deep soft mud in water or slush
- misch metal
- a pyrophoric alloy made from a mixture of rare-earth metals
- mitogen
- an agent that triggers mitosis
- mixture
- (chemistry) a substance consisting of two or more substances mixed together (not in fixed proportions and not with chemical bonding)
- Mn
- a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals
- Mo
- a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel
- mocha
- soft suede glove leather from goatskin
- moderator
- any substance used to slow down neutrons in nuclear reactors
- mold
- loose soil rich in organic matter
- molecule
- (physics and chemistry) the simplest structural unit of an element or compound
- Molisch reaction
- biochemical indicator of the presence of carbohydrates in a solution; if carbohydrates are present a violet ring is formed by reaction with alpha-naphthol in the presence of sulfuric acid
- molybdenite
- a mineral resembling graphite that is valued as the chief source of molybdenum and its compounds
- molybdenum steel
- steel containing 10-15% molybdenum; properties are similar to tungsten steel
- monad
- (chemistry) an atom having a valence of one
- monazite
- a reddish-brown mineral containing rare earth metals; an important source of thorium and cerium
- Monell metal
- an alloy of nickel and copper and other metals (such as iron and/or manganese and/or aluminum)
- mono-iodotyrosine
- tyrosine with one iodine atom added
- monoamine
- a molecule containing one amine group (especially one that is a neurotransmitter)
- monoamine neurotransmitter
- a monoamine that is functionally important in neural transmission
- monobasic acid
- an acid containing only one replaceable hydrogen atom per molecule
- monoclonal
- any of a class of antibodies produced in the laboratory by a single clone of cells or a cell line and consisting of identical antibody molecules
- monohydrate
- a hydrate that contains one molecule of water per molecule of the compound
- monomer
- a simple compound whose molecules can join together to form polymers
- monosaccharide
- a sugar (like sucrose or fructose) that does not hydrolyse to give other sugars; the simplest group of carbohydrates
- monounsaturated fatty acid
- an unsaturated fatty acid whose carbon chain has one double or triple valence bond per molecule; found chiefly in olive oil and chicken and almonds
- monoxide
- an oxide containing just one atom of oxygen in the molecule
- montan wax
- a hard wax obtained from lignite
- moonstone
- a transparent or translucent gemstone with a pearly luster; some specimens are orthoclase feldspar and others are plagioclase feldspar
- mordant
- a substance used to treat leather or other materials before dyeing; aids in dyeing process
- morganite
- a kind of pink beryl used as a gemstone
- morocco
- a soft pebble-grained leather made from goatskin; used for shoes and book bindings etc.
- mortar
- used as a bond in masonry or for covering a wall
- mosaic gold
- a yellow pigment sometimes suspended in lacquer
- moss agate
- an agate resembling moss with brown, black, or green markings
- mother
- a stringy slimy substance consisting of yeast cells and bacteria; forms during fermentation and is added to cider or wine to produce vinegar
- mother-of-pearl
- the iridescent internal layer of a mollusk shell
- motor oil
- oil used to lubricate the moving parts of a motor
- MSH
- a hormone secreted by the anterior pituitary gland that controls the degree of pigmentation in melanocytes
- Mt
- a radioactive transuranic element
- mucic acid
- a solid acid (C6H10O8) found in milk or sugar
- mucilage
- a gelatinous substance secreted by plants
- mucin
- a nitrogenous substance found in mucous secretions; a lubricant that protects body surfaces
- mucoid
- any of several glycoproteins similar to mucin
- mucopolysaccharide
- complex polysaccharides containing an amino group; occur chiefly as components of connective tissue
- mud pie
- a mass of mud that a child has molded into the shape of pie
- Muntz metal
- a brass that has more zinc and is stronger than alpha brass; used in making castings and hot-worked products
- muriatic acid
- a former name for hydrochloric acid
- muscovite
- a colorless or pale brown mica with potassium
- music paper
- paper with lines appropriate for writing music
- musk
- an odorous glandular secretion from the male musk deer; used as a perfume fixative
- muskrat
- the brown fur of a muskrat
- muton
- the smallest unit of DNA where a mutation can occur
- mutton tallow
- tallow from the body of a mature sheep
- Mv
- a radioactive transuranic element synthesized by bombarding einsteinium with alpha particles (Md is the current symbol for mendelevium but Mv was formerly the symbol)
- mycotoxin
- a toxin produced by a fungus
- Mylanta
- an antacid
- Mylar
- a thin polyester film
- myoglobin
- a hemoprotein that receives oxygen from hemoglobin and stores it in the tissues until needed
- myosin
- the commonest protein in muscle; a globulin that combines with actin to form actomyosin
- myristic acid
- a saturated fatty acid occurring naturally in animal and vegetable fats
- N
- a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
- Na
- a silvery soft waxy metallic element of the alkali metal group; occurs abundantly in natural compounds (especially in salt water); burns with a yellow flame and reacts violently in water; occurs in sea water and in the mineral halite (rock salt)
- NAD
- a coenzyme present in most living cells and derived from the B vitamin nicotinic acid; serves as a reductant in various metabolic processes
- NADP
- a coenzyme similar to NAD and present in most living cells but serves as a reductant in different metabolic processes
- napalm
- gasoline jelled with aluminum soaps; highly incendiary liquid used in fire bombs and flamethrowers
- naphtha
- any of various volatile flammable liquid hydrocarbon mixtures; used chiefly as solvents
- naphthalene
- a white crystalline strong-smelling hydrocarbon made from coal tar or petroleum and used in organic synthesis and as a fumigant in mothballs
- naphthol
- either of two phenols derived from naphthalene
- natrolite
- a group of minerals of the zeolite family consisting of a hydrous silicate of sodium and aluminum
- natural fiber
- fiber derived from plants or animals
- natural glass
- magma of any composition that cooled very rapidly
- natural resin
- a plant exudate
- Nb
- a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium
- Nd
- a yellow trivalent metallic element of the rare earth group; occurs in monazite and bastnasite in association with cerium and lanthanum and praseodymium
- Ne
- a colorless odorless gaseous element that give a red glow in a vacuum tube; one of the six inert gasses; occurs in the air in small amounts
- neat's-foot oil
- a pale yellow oil made from the feet and legs of cattle; used as a dressing for leather
- nebula
- a medicinal liquid preparation intended for use in an atomizer
- nectar
- a sweet liquid secretion that is attractive to pollinators
- neem cake
- residue after oil is pressed from neem seeds
- neoprene
- a synthetic rubber that is resistant to oils and aging; used in waterproof products
- nepheline
- a whitish mineral consisting of sodium aluminum silicate or potassium aluminum silicate in crystalline form; used in the manufacture of ceramics and enamels
- nephelinite
- an igneous rock consisting of nepheline and pyroxene
- nephrite
- an amphibole mineral consisting of calcium magnesium silicate in monoclinic crystalline form; a source of jade that is less valuable than from jadeite; once believed to cure kidney disorders
- nephrotoxin
- any toxin that affects the kidneys
- neroli oil
- an odoriferous yellow oil found in orange flowers and used in perfumery and as a flavoring
- nerve agent
- a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system
- neurochemical
- any organic substance that occurs in neural activity
- neurolysin
- any toxin that affects neural tissues
- neuromuscular blocking agent
- a substance that interferes with the neural transmission between motor neurons and skeletal muscles
- neurotransmitter
- a neurochemical that transmits nerve impulses across a synapse
- newspaper
- cheap paper made from wood pulp and used for printing newspapers
- NGF
- a protein that is involved in the growth of peripheral nerve cells
- Ni
- a hard malleable ductile silvery metallic element that is resistant to corrosion; used in alloys; occurs in pentlandite and smaltite and garnierite and millerite
- Ni-hard iron
- cast iron to which nickel has been added to make it resist abrasion
- Ni-resist iron
- cast iron consisting of graphite in a matrix of austenite
- niacin
- a B vitamin essential for the normal function of the nervous system and the gastrointestinal tract
- Nichrome
- an alloy of nickel and chromium with high electrical resistance and an ability to withstand high temperatures; used for resistance heating elements
- nickel alloy
- an alloy whose main constituent is nickel
- nickel bronze
- a bronze containing up to 30% nickel
- nickel steel
- an alloy steel containing nickel
- nicotine
- an alkaloid poison that occurs in tobacco; used in medicine and as an insecticide
- night soil
- human excreta used as fertilizer
- niter
- (KNO3) used especially as a fertilizer and explosive
- nitramine
- a yellow crystalline explosive solid that is used in detonators
- nitrate
- any compound containing the nitrate group (such as a salt or ester of nitric acid)
- nitric oxide
- a poisonous red-brown gas (NO)
- nitride
- a compound containing nitrogen and a more electropositive element (such as phosphorus or a metal)
- nitrite
- the radical -NO2 or any compound containing it (such as a salt or ester of nitrous acid)
- nitro group
- the group -NO3
- nitrobenzene
- a poisonous oily water-soluble liquid used as a solvent and in the manufacture of aniline
- nitrocalcite
- the mineral form of calcium nitrate
- nitrochloromethane
- gaseous form of chloropicrin used as tear gas
- nitrofuran
- derivative of furan used to inhibit bacterial growth
- nitrogen dioxide
- a highly poisonous brown gas (NO2)
- nitrogen mustard
- a toxic compound resembling mustard gas in structure; important in cancer treatment
- nitrogen oxide
- any of several oxides of nitrogen formed by the action of nitric acid on oxidizable materials; present in car exhausts
- nitrogenase
- an enzyme of nitrogen-fixing microorganisms that catalyzes the conversion of nitrogen to ammonia
- Nitrostat
- a heavy yellow poisonous oily explosive liquid obtained by nitrating glycerol; used in making explosives and medically as a vasodilator (trade names Nitrospan and Nitrostat)
- nitrous acid
- an unstable inorganic acid known only in solution and as nitrite salts
- No
- a radioactive transuranic element synthesized by bombarding curium with carbon ions; 7 isotopes are known
- noble metal
- any metal that is resistant to corrosion or oxidation
- noncoding DNA
- sequence of a eukaryotic gene's DNA that is not translated into a protein
- nonmetal
- a chemical element lacking typical metallic properties
- nonsteroid
- an organic compound that does no contain a steroid
- norethynodrel
- a progesterone derivative used in oral contraceptives and in the control of menstruation and the treatment of abnormal uterine bleeding
- norgestrel
- synthetic progestin used in oral contraceptives
- Norlutin
- a synthetic progestational hormone (trade name Norlutin) used in oral contraceptives and to treat endometriosis
- notepad
- a pad of paper for keeping notes
- Np
- a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium
- nuclear fuel
- fuel (such as uranium) that can be used in nuclear reactors as a source of electricity
- nuclear RNA
- ribonucleic acid found in the nucleolus of the cell
- nuclease
- general term for enzymes that catalyze the hydrolysis of nucleic acid by cleaving chains of nucleotides into smaller units
- nucleic acid
- (biochemistry) any of various macromolecules composed of nucleotide chains that are vital constituents of all living cells
- nucleoprotein
- any of several substances found in the nuclei of all living cells; consists of a protein bound to a nucleic acid
- nucleoside
- a glycoside formed by partial hydrolysis of a nucleic acid
- nurse log
- a large decomposing tree trunk that has fallen, usually in a forest; the decaying wood provides moisture and nutrients for a variety of insects and plants
- nylon
- a thermoplastic polyamide; a family of strong resilient synthetic fibers
- O
- a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
- oakum
- loose hemp or jute fiber obtained by unravelling old ropes; when impregnated with tar it was used to caulk seams and pack joints in wooden ships
- obidoxime chloride
- a chloride used as an antidote for nerve gases such as sarin or VX
- obsidian
- acid or granitic glass formed by the rapid cooling of lava without crystallization; usually dark, but transparent in thin pieces
- ocher
- any of various earths containing silica and alumina and ferric oxide; used as a pigment
- octadecanoic acid
- a waxy saturated fatty acid; occurs widely as a glyceride in animal and vegetable fats
- octane
- any isomeric saturated hydrocarbon found in petroleum and used as a fuel and solvent
- octanedioic acid
- a dicarboxylic acid found in cork
- oil
- a slippery or viscous liquid or liquefiable substance not miscible with water
- oil of turpentine
- volatile liquid distilled from turpentine oleoresin; used as paint thinner and solvent and medicinally
- oil of vitriol
- (H2SO4) a highly corrosive acid made from sulfur dioxide; widely used in the chemical industry
- oil shale
- shale from which oil can be obtained by heating
- oil-hardened steel
- steel that is quenched in oil
- oilpaper
- paper that has been made translucent and waterproof by soaking in oil
- ola
- leaf or strip from a leaf of the talipot palm used in India for writing paper
- oleic acid
- a colorless oily liquid occurring as a glyceride; it is the major fatty acid in olive oil and canola oil; used in making soap and cosmetics and ointments and lubricating oils
- olein
- a naturally occurring glyceride of oleic acid that is found in fats and oils
- oleo oil
- obtained from beef fat; used in making margarine and soap and in lubrication
- oleoresin
- a naturally occurring mixture of a resin and an essential oil; obtained from certain plants
- oleoresin capiscum
- an oleoresin extracted from the capsicum pepper plant
- oligo
- (biochemistry) a polynucleotide whose molecules contain relatively few nucleotides
- oligoclase
- any of a series of triclinic feldspars that form rocks
- oligosaccharide
- any of the carbohydrates that yield only a few monosaccharide molecules on complete hydrolysis
- olivenite
- rare green to black mineral consisting of hydrated copper arsenate that is found in copper deposits
- olivine
- a mineral consisting of magnesium iron silicate; a source of magnesium
- omega-3
- a polyunsaturated fatty acid whose carbon chain has its first double valence bond three carbons from the beginning
- omega-6
- a polyunsaturated fatty acid whose carbon chain has its first double valence bond six carbons from the beginning
- onyx
- a chalcedony with alternating black and white bands; used in making cameos
- ooze leather
- a very soft leather made from the skins of calves and having a suede finish on the flesh side
- opal
- a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones
- opaque gem
- a gemstone that is opaque
- opopanax
- an odorous gum resin formerly used in medicines
- opsin
- retinal protein formed by the action of light on rhodopsin
- opsonin
- an antibody in blood serum that attaches to invading microorganisms and other antigens to make them more susceptible to the action of phagocytes
- optical glass
- clear homogeneous glass of known refractive index; used to make lenses
- orange
- any pigment producing the orange color
- ore
- a mineral that contains metal that is valuable enough to be mined
- oreide
- alloy of copper and tin and zinc; used in imitation gold jewelry
- organic compound
- any compound of carbon and another element or a radical
- organic
- a fertilizer that is derived from animal or vegetable matter
- organophosphate
- an insecticide that interferes with an insect's nervous system
- organophosphate nerve agent
- any of a series of nerve agents containing organophosphate compounds first synthesized by German chemists in 1936; in World War II the Germans tested them in concentration camps but not on the battlefield; Iraq is alleged to have used them against Iran and against the Kurds
- ormolu
- brass that looks like gold; used to decorate furniture
- ornithine
- an amino acid that does not occur in proteins but is important in the formation of urea
- orpiment
- a yellow mineral occurring in conjunction with realgar; an ore of arsenic
- orthoclase
- a white or colored monoclinic feldspar
- orthophosphoric acid
- an acid used in fertilizers and soaps: H3PO4
- Os
- a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known
- Otaheite arrowroot starch
- a starch obtained from the root of the pia
- otter
- the fur of an otter
- oxalacetate
- a salt or ester of oxalacetic acid
- oxalacetic acid
- an acid formed by oxidation of maleic acid (as in metabolism of fats and carbohydrates)
- oxalate
- a salt or ester of oxalic acid
- oxidant
- a substance that oxidizes another substance
- oxidase
- any of the enzymes that catalyze biological oxidation
- oxidation-reduction indicator
- an indicator that shows a reversible color change between oxidized and reduced forms
- oxide
- any compound of oxygen with another element or a radical
- oxidized LDL cholesterol
- LDL cholesterol that has been bombarded by free radicals; it is thought to cause atherosclerosis
- oxidoreductase
- an enzyme that catalyzes oxidation-reduction
- oxime
- any compound containing the group -C=NOH
- oxyacetylene
- a mixture of oxygen and acetylene; used to create high temperatures for cutting or welding metals
- oxyacid
- any acid that contains oxygen
- oxygenase
- an oxidoreductase that catalyzes the incorporation of molecular oxygen
- oxyhaemoglobin
- the bright red hemoglobin that is a combination of hemoglobin and oxygen from the lungs
- ozone
- a colorless gas (O3) soluble in alkalis and cold water; a strong oxidizing agent; can be produced by electric discharge in oxygen or by the action of ultraviolet radiation on oxygen in the stratosphere (where it acts as a screen for ultraviolet radiation)
- ozonide
- any of a class of unstable chemical compounds resulting from the addition of ozone to a double bond in an unsaturated compound
- P
- a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms
- Pa
- a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead
- PABA
- a metabolic acid found in yeast and liver cells; used to make dyes and drugs and sun blockers
- packing
- any material used especially to protect something
- pad
- a number of sheets of paper fastened together along one edge
- pahoehoe
- freely flowing lava
- palmitin
- an ester of glycerol and palmitic acid
- pancreatin
- extract from the pancreas of animals that contains pancreatic enzymes; used to treat pancreatitis and other conditions involving insufficient pancreatic secretions
- pantile
- a roofing tile with a S-shape; laid so that curves overlap
- pantothen
- a vitamin of the vitamin B complex that performs an important role in the oxidation of fats and carbohydrates and certain amino acids; occurs in many foods
- papain
- a proteolytic enzyme obtained from the unripe papaya; used as a meat tenderizer
- paper
- a material made of cellulose pulp derived mainly from wood or rags or certain grasses
- paper tape
- a long narrow strip of paper
- paper toweling
- absorbent paper used as toweling
- paper-mache
- a substance made from paper pulp that can be molded when wet and painted when dry
- paperboard
- a cardboard suitable for making posters
- papyrus
- paper made from the papyrus plant by cutting it in strips and pressing it flat; used by ancient Egyptians and Greeks and Romans
- Para rubber
- a type of natural rubber obtained from tropical South American trees
- paraffin scale
- partly refined paraffin wax
- paraffin
- (British usage) kerosine
- paraffin
- from crude petroleum; used for candles and for preservative or waterproof coatings
- paragonite
- a colorless or pale brown mica with sodium
- paraquat
- a poisonous yellow solid used in solution as a herbicide
- parathion
- a colorless and odorless toxic oil used as an insecticide
- parchment
- a superior paper resembling sheepskin
- parget
- plaster used to coat outer walls and line chimneys
- Paris green
- a toxic double salt of copper arsenate and copper acetate
- particulate
- a small discrete mass of solid or liquid matter that remains individually dispersed in gas or liquid emissions (usually considered to be an atmospheric pollutant)
- paste
- a hard, brilliant lead glass that is used in making artificial jewelry
- paste
- any mixture of a soft and malleable consistency
- pasteboard
- stiff cardboard made by pasting together layers of paper
- patent leather
- leather with a hard glossy surface
- pavement
- material used to pave an area
- pay dirt
- ore that yields a substantial profit to the miner
- Payne's grey
- any pigment that produces a greyish to dark greyish blue
- Pb
- a soft heavy toxic malleable metallic element; bluish white when freshly cut but tarnishes readily to dull grey
- PBS
- a solution containing a phosphate buffer
- Pd
- a silver-white metallic element of the platinum group that resembles platinum; occurs in some copper and nickel ores; does not tarnish at ordinary temperatures and is used (alloyed with gold) in jewelry
- pearl ash
- an impure form of potassium carbonate
- pearl sago
- sago ground into small round grains
- pearlite
- a lamellar mixture of cementite and ferrite formed during the cooling of austenite; a constituent of steel and cast iron
- peat
- partially carbonized vegetable matter saturated with water; can be used as a fuel when dried
- pectic acid
- a complex acid that occurs in ripe fruit and some vegetables
- pectin
- any of various water-soluble colloidal carbohydrates that occur in ripe fruit and vegetables; used in making fruit jellies and jams
- Pediapred
- a glucocorticoid (trade names Pediapred or Prelone) used to treat inflammatory conditions
- pediculicide
- a chemical agent that kills lice
- pee
- liquid excretory product
- pegmatite
- a form of igneous rock consisting of extremely coarse granite resulting from the crystallization of magma rich in rare elements
- pencil
- graphite (or a similar substance) used in such a way as to be a medium of communication
- pentanoic acid
- a clear liquid carboxylic acid used in perfumes and drugs
- pentlandite
- a mineral (iron and nickel sulphide) that is the chief ore of nickel
- pentose
- any monosaccharide sugar containing five atoms of carbon per molecule
- pentoxide
- an oxide containing five atoms of oxygen in the molecule
- pepsin
- an enzyme produced in the stomach that splits proteins into peptones
- pepsinogen
- precursor of pepsin; stored in the stomach walls and converted to pepsin by hydrochloric acid in the stomach
- peptidase
- any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis
- peptide
- amide combining the amino group of one amino acid with the carboxyl group of another; usually obtained by partial hydrolysis of protein
- Pepto-bismal
- an antacid
- peptone
- any of various water-soluble compounds that form by hydrolysis in the digestion of proteins to amino acids
- perboric acid
- a form of boric acid
- perchlorate
- a salt of perchloric acid
- perchloric acid
- a powerful oxidizing agent; forms perchlorates
- perchloride
- a chloride containing an unusually high proportion of chlorine
- percolate
- the product of percolation
- peridot
- a pale green variety of chrysolite; used as a gemstone
- peridotite
- a dark coarse-grained igneous rock consisting principally of olivine
- periodic acid
- any acid of iodine that contains oxygen
- Permalloy
- an 80/20 alloy of nickel and iron; easily magnetized and demagnetized
- permanganate
- a dark purple salt of permanganic acid; in water solution it is used as a disinfectant and antiseptic
- permanganate of potash
- a poisonous salt that forms dark purple crystals and is purple-red when dissolved in water; used as an oxidizing and bleaching agent and as a disinfectant and antiseptic
- permanganic acid
- an unstable purple acid (HMnO4) known only in solution or of permanganate salts
- peroxidase
- any of a group of enzymes (occurring especially in plant cells) that catalyze the oxidation of a compound by a peroxide
- peroxide
- an inorganic compound containing the divalent ion -O-O-
- Persian lamb
- the fur of a karakul lamb
- Perspex
- a transparent thermoplastic acrylic resin
- pesticide
- a chemical used to kill pests (as rodents or insects)
- petrochemical
- any compound obtained from petroleum or natural gas
- pewter
- any of various alloys of tin with small amounts of other metals (especially lead)
- PFC
- a powerful greenhouse gas emitted during the production of aluminum
- pheno-safranine
- a purplish red water-soluble dye used in microscopy
- phenol
- any of a class of weakly acidic organic compounds; molecule contains one or more hydroxyl groups
- phenolic plastic
- a plastic consisting of phenolic resins
- phenolic
- a thermosetting resin
- phenothiazine
- a compound used primarily in veterinary medicine to rid farm animals of internal parasites
- phenyl salicylate
- a white powder with a pleasant taste and odor; used to absorb light in sun tan lotions or as a preservative or an antiseptic or a coating for pills in which the medicine is intended for enteric release
- phenylalanine
- an essential amino acid found in proteins and needed for growth of children and for protein metabolism in children and adults; abundant in milk and eggs; it is normally converted to tyrosine in the human body
- pheromone
- a chemical substance secreted externally by some animals (especially insects) that influences the physiology or behavior of other animals of the same species
- phillipsite
- a group of white or reddish crystalline minerals of the zeolite family consisting of a hydrous silicate of calcium and potassium and aluminum
- phlogiston
- a hypothetical substance once believed to be present in all combustible materials and to be released during burning
- phlogopite
- a brown form of mica consisting of hydrous silicate of potassium and magnesium and aluminum
- phosgene
- a colorless poisonous gas that smells like new-mown hay; used in chemical warfare
- phosphatase
- any of a group of enzymes that act as a catalyst in the hydrolysis of organic phosphates
- phosphine
- a colorless gas with a strong fishy smell; used as a pesticide
- phospholipid
- any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base; an important constituent of membranes
- phosphoprotein
- containing chemically bound phosphoric acid
- phosphor
- a synthetic substance that is fluorescent or phosphorescent; used to coat the screens of cathode ray tubes
- phosphor bronze
- a corrosion-resistant bronze containing phosphorus; used in bearings and gears
- photopigment
- a special pigment found in the rods and cones of the retina
- phthalic acid
- a colorless acid used to make dyes and perfumes
- phthalic anhydride
- a white cyclic anhydride
- phytochemical
- a chemical substance obtained from plants that is biologically active but not nutritive
- phytotoxin
- any substance produced by plants that is similar in its properties to extracellular bacterial toxin
- picric acid
- a yellow toxic highly explosive strong acid; used in high explosives and as a dye and in chemical reactions
- pig iron
- crude iron tapped from a blast furnace
- pig lead
- lead that is cast in pigs
- pigeon droppings
- droppings of pigeons
- pigment
- dry coloring material (especially a powder to be mixed with a liquid to produce paint, etc.)
- pigment
- any substance whose presence in plant or animal tissues produces a characteristic color
- pigskin
- leather from the skin of swine
- pillow lava
- lava that hardened in rounded shapes suggestive of pillows; believed to result from underwater eruptions
- pina cloth
- a fine cloth made from pineapple fibers
- pinchbeck
- an alloy of copper and zinc that is used in cheap jewelry to imitate gold
- pine knot
- a joint of pine wood used for fuel
- pine tar
- a dark viscous substance obtained from the destructive distillation of pine wood
- pinite
- grey or green or brown mineral similar to mica and containing aluminum and potassium sulphates
- pipeclay
- fine white clay used in making tobacco pipes and pottery and in whitening leather
- piperin
- derived from pepper (especially black pepper); source of the hotness of black and white pepper
- pisang wax
- a wax obtained from the leaves of a plantain
- pitch
- any of various dark heavy viscid substances obtained as a residue
- pitchblende
- a mineral consisting of uranium oxide and trace amounts of radium and thorium and polonium and lead and helium; uraninite in massive form is called pitchblende which is the chief uranium ore
- pitchstone
- dark acid granitic glass
- planking
- planks collectively; a quantity of planks
- plant fiber
- fiber derived from plants
- plant material
- material derived from plants
- plant product
- a product made from plant material
- plasma
- a green slightly translucent variety of chalcedony used as a gemstone
- plasma protein
- any of the proteins in blood plasma
- plasminogen
- an inactive form of plasmin that occurs in plasma and is converted to plasmin by organic solvents
- plasminogen activator
- protease produced in the kidney that converts plasminogen to plasmin and so initiates fibrinolysis
- plaster
- a mixture of lime or gypsum with sand and water; hardens into a smooth solid; used to cover walls and ceilings
- plaster of Paris
- any of several gypsum cements; a white powder (a form of calcium sulphate) that forms a paste when mixed with water and hardens into a solid; used in making molds and sculptures and casts for broken limbs
- plastic
- generic name for certain synthetic or semisynthetic materials that can be molded or extruded into objects or films or filaments or used for making e.g. coatings and adhesives
- Plasticine
- a synthetic material resembling clay but remaining soft; used as a substitute for clay or wax in modeling (especially in schools)
- plasticiser
- a substance added to plastics or other materials to make them more pliable
- platinum black
- a fine black powder of platinum; used as a catalyst in chemical reactions
- Plexiglas
- a light transparent weather resistant thermoplastic
- plutonium 239
- a highly fissionable isotope of plutonium that is used in atomic weapons and as a reactor fuel; produced by irradiating uranium 238 with slow electrons
- Pm
- a soft silvery metallic element of the rare earth group having no stable isotope; was discovered in radioactive form as a fission product of uranium
- Po
- a radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor
- podsol
- a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer
- poison gas
- a gas that is poisonous to breath or contact; used in chemical warfare
- poison
- any substance that causes injury or illness or death of a living organism
- polish
- a preparation used in polishing
- pollucite
- a rare mineral that is an important source of cesium
- pollutant
- waste matter that contaminates the water or air or soil
- polyamide
- a polymer containing repeated amide groups
- polybutene
- a polymer of butylene; used in lubricants and synthetic rubber
- polyelectrolyte
- an electrolyte of high molecular weight
- polyester
- a complex ester used for making fibers or resins or plastics or as a plasticizer
- polyester
- any of numerous synthetic resins; they are light and strong and weather resistant
- polyester fiber
- a quick-drying resilient synthetic fiber consisting primarily of polyester
- polyethylene
- a lightweight thermoplastic; used especially in packaging and insulation
- polyfoam
- a foam made by adding water to polyurethane plastics
- polymer
- a naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers
- polymerase
- an enzyme that catalyzes the formation of new DNA and RNA from an existing strand of DNA or RNA
- polymethyl methacrylate
- a transparent plastic used as a substitute for glass
- polynucleotide
- (biochemistry) a linear polymer whose molecule is composed of many nucleotide units constituting a section of a nucleic acid molecule
- polyose
- any of a class of carbohydrates whose molecules contain chains of monosaccharide molecules
- polypeptide
- a peptide containing 10 to more than 100 amino acids
- polyphosphate
- a salt or ester of polyphosphoric acid
- polyphosphoric acid
- a series of oxyacids of phosphorus
- polypropene
- a polymer of propylene used as a thermoplastic molding material
- polystyrene
- a polymer of styrene; a rigid transparent thermoplastic
- polyunsaturated fat
- a class of fats having long carbon chains with many double bonds unsaturated with hydrogen atoms; used in some margarines; supposedly associated with low blood cholesterol
- polyunsaturated fatty acid
- an unsaturated fatty acid whose carbon chain has more than one double or triple valence bond per molecule; found chiefly in fish and corn and soybean oil and safflower oil
- polyurethan
- any of various polymers containing the urethane radical; a wide variety of synthetic forms are made and used as adhesives or plastics or paints or rubber
- polyvinyl resin
- a thermoplastic derived by polymerization from compounds containing the vinyl group
- polyvinyl-formaldehyde
- a polymer of vinyl formaldehyde
- porphyrin
- any of various pigments distributed widely in living tissues
- porphyritic rock
- any igneous rock with crystals embedded in a finer groundmass of minerals
- porpoise oil
- a yellow fatty oil obtained from porpoises and used as a fine lubricant
- Portland cement
- a cement that hardens under water; made by heating limestone and clay in a kiln and pulverizing the result
- pot metal
- cast iron used for making cooking wares
- pot metal
- an alloy of copper and lead used especially for making large pots
- potassium acid carbonate
- a crystalline salt (KHCO3) that is used in baking powder and as an antacid
- potassium bromide
- a white crystalline salt (KBr) used as a sedative and in photography
- potassium carbonate
- a white salt (K2CO3) that is basic in solution; used to make glass and cleansing agents
- potassium chlorate
- a white salt (KClO3) used in matches, fireworks, and explosives; also used as a disinfectant and bleaching agent
- potassium cyanide
- a poisonous salt (KCN) used in electroplating and in photography
- potassium dichromate
- an orange-red salt used in making dyes and in photography
- potassium ferrocyanide
- a cyanide compound that is prepared by the reaction of potassium cyanide with ferrous salts; commonly used by gardeners
- potassium iodide
- a crystalline salt in organic synthesis and in making photographic emulsions and in iodized table salt
- potter's clay
- clay that does not contain any iron; used in making pottery or for modeling
- powder
- a solid substance in the form of tiny loose particles; a solid that has been pulverized
- Pr
- a soft yellowish-white trivalent metallic element of the rare earth group; can be recovered from bastnasite or monazite by an ion-exchange process
- prairie soil
- a type of soil occurring under grasses in temperate climates
- precipitant
- an agent that causes a precipitate to form
- precipitate
- a precipitated solid substance in suspension or after settling or filtering
- precipitin
- an antibody that causes precipitation when it unites with its antigen
- precursor
- a substance from which another substance is formed (especially by a metabolic reaction)
- pregnanediol
- a compound found in women's urine during certain phases of the menstrual cycle and in the urine of pregnant women
- preservative
- a chemical compound that is added to protect against decay or decomposition
- Prevacid
- antacid (trade name Prevacid) that suppresses acid secretion in the stomach
- Prilosec
- antacid (trade name Prilosec) that suppresses acid secretion in the stomach
- primary solid solution
- a homogeneous solid that can exist over a range of component chemicals; a constituent of alloys that is formed when atoms of an element are incorporated into the crystals of a metal
- printer's ink
- a semisolid quick drying ink made especially for use in printing
- product
- a chemical substance formed as a result of a chemical reaction
- proenzyme
- any of a group of compounds that are inactive precursors of enzymes and require some change (such as the hydrolysis of a fragment that masks an active enzyme) to become active
- progestin
- any of a group of steroid hormones that have the effect of progesterone
- prolamine
- a simple protein found in plants
- proline
- an amino acid that is found in many proteins (especially collagen)
- propanal
- a colorless liquid aldehyde
- propanamide
- the amide of propionic acid (C2H5CONH2)
- propane
- colorless gas found in natural gas and petroleum; used as a fuel
- propanediol
- a sweet colorless, viscous, hygroscopic liquid used as an antifreeze and in brake fluid and also as a humectant in cosmetics and personal care items although it can be absorbed through the skin with harmful effects
- propanoic acid
- a liquid fatty acid found in milk and sweat and in fuel distillates
- propanol
- a clear colorless volatile liquid (alcohol) used as a solvent and antiseptic
- propellant
- any substance that propels
- propene
- a flammable gas obtained by cracking petroleum; used in organic synthesis
- propyl
- the monovalent organic group C3H7- obtained from propane
- propylthiouracil
- a crystalline compound used as an antithyroid drug in the treatment of goiter
- protamine
- a simple protein found in fish sperm; rich in arginine; simpler in composition than globulin or albumin; counteracts the anticoagulant effect of heparin
- protein
- any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes
- proteome
- the full complement of proteins produced by a particular genome
- Provera
- a progestin compound (trade name Provera) used to treat menstrual disorders
- provirus
- cDNA copy of the RNA genome of a retrovirus; the genetic material of a virus as incorporated into and able to replicate with the genome of a host cell
- provitamin
- vitamin precursor; a substance that is converted into a vitamin in animal tissues
- provitamin A
- an orange isomer of an unsaturated hydrocarbon found in many plants; is converted into vitamin A in the liver
- Prussian blue
- any of various blue pigments
- PSA
- a protein manufactured exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm cells to swim freely; elevated levels of PSA in blood serum are associated with benign prostatic hyperplasia and prostate cancer
- pseudoephedrine
- poisonous crystalline alkaloid occurring with ephedrine and isomorphic with it
- psilomelane
- a mineral consisting of hydrated basic oxide of manganese and barium; a source of manganese
- Pt
- a heavy precious metallic element; grey-white and resistant to corroding; occurs in some nickel and copper ores and is also found native in some deposits
- ptomain
- any of various amines (such as putrescine or cadaverine) formed by the action of putrefactive bacteria
- ptyalin
- an amylase secreted in saliva
- Pu
- a solid silvery grey radioactive transuranic element whose atoms can be split when bombarded with neutrons; found in minute quantities in uranium ores but is usually synthesized in nuclear reactors; 13 isotopes are known with the most important being plutonium 239
- puddle
- a mixture of wet clay and sand that can be used to line a pond and that is impervious to water when dry
- pulp
- a mixture of cellulose fibers
- pulpwood
- softwood used to make paper
- pumice
- a light glass formed on the surface of some lavas; used as an abrasive
- punk
- substance that smolders when ignited; used to light fuses (especially fireworks)
- purine
- a colorless crystalline organic base containing nitrogen; the parent compound of various biologically important substances
- purine
- any of several bases that are derivatives of purine
- putrescine
- a colorless crystalline ptomaine with a foul odor that is produced in decaying animal matter
- putty
- a dough-like mixture of whiting and boiled linseed oil; used especially to patch woodwork or secure panes of glass
- PVA
- a vinyl polymer used especially in paints or adhesives
- PVC
- a polymer of vinyl chloride used instead of rubber in electric cables
- pyrectic
- any substance that can cause a rise in body temperature
- pyrene
- a pale yellow crystalline hydrocarbon C16H10 extracted from coal tar
- Pyrex
- a borosilicate glass with a low coefficient of expansion; used for heat-resistant glassware in cooking and chemistry
- pyridine
- a toxic colorless flammable liquid organic base with a disagreeable odor; usually derived from coal
- pyrimidine
- a heterocyclic organic compound with a penetrating odor
- pyrimidine
- any of several basic compounds derived from pyrimidine
- pyrites
- any of various metallic-looking sulfides (of which pyrite is the commonest)
- pyrocellulose
- nitrocellulose containing less nitrogen than guncotton; used in making smokeless powder
- pyrogallic acid
- a toxic white lustrous crystalline phenol used to treat certain skin diseases and as a photographic developer
- pyrogen
- any substance characterized by its great flammability
- pyroligneous acid
- a red-brown liquid formed in distillation of wood which contains acetic acid, methanol, acetone, wood oils, and tars
- pyrolusite
- a mineral consisting of manganese dioxide; an important source of manganese
- pyrope
- a deep red garnet used as a gemstone
- pyrophoric alloy
- an alloy that emits sparks when struck or scratched with steel; used in lighter flints
- pyrophosphate
- a salt or ester of pyrophosphoric acid
- pyrophosphoric acid
- a solid acid formed by reactions of orthophosphoric acid
- pyrophyllite
- a white or greenish aluminum silicate mineral (resembles talc)
- pyroxene
- any of a group of crystalline silicate mineral common in igneous and metamorphic rocks
- pyroxylin
- highly flammable nitrocellulose used in making collodion and plastics and lacquers
- pyruvic acid
- a colorless acid formed as an important intermediate in metabolism or fermentation
- quartz
- a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities
- quartzite
- hard metamorphic rock consisting essentially of interlocking quartz crystals
- quassia
- a bitter compound used as an insecticide and tonic and vermifuge; extracted from the wood and bark of trees of the genera Quassia and Picrasma
- quaternary ammonium compound
- a compound derived from ammonium with hydrogen atoms replaced by organic groups; used as surface-active agents, disinfectants, and in drugs
- quenched steel
- steel that has been hardened by immersing it in water or oil to cool it
- quercitron
- a yellow dye made from the bark of the quercitron oak tree
- Ra
- an intensely radioactive metallic element that occurs in minute amounts in uranium ores
- raccoon
- the fur of the North American racoon
- racemic acid
- the optically inactive form of tartaric acid that is often found in grape juice
- raddle
- a red iron ore used in dyeing and marking
- radioactive material
- material that is radioactive
- radioactive waste
- useless radioactive materials that are left after some laboratory or commercial process is completed
- radiochlorine
- a radioactive isotope of chlorine
- radioisotope
- a radioactive isotope of an element; produced either naturally or artificially
- radiopaque dye
- dye that does not allow the passage of X rays or other radiation; used to outline certain organs during X-ray examination
- radiothorium
- radioactive isotope of thorium with mass number 228
- raffia
- leaf fibers of the raffia palm tree; used to make baskets and mats etc.
- raffinose
- a trisaccharide that occurs in sugar beets and cotton seeds and certain cereals
- rag paper
- paper made partly or wholly from rags
- ragweed pollen
- pollen of the ragweed plant is a common allergen
- rain
- drops of fresh water that fall as precipitation from clouds
- rauwolfia
- any of several alkaloids extracted from the shrub Rauwolfia serpentina
- raveling
- a bit of fiber that has become separated from woven fabric
- raw material
- material suitable for manufacture or use or finishing
- raw sienna
- a yellowish-brown pigment made from untreated sienna
- raw umber
- greenish brown pigment
- raw wood
- wood that is not finished or painted
- raw wool
- wool in its natural condition; not refined or processed
- rawhide
- untanned hide especially of cattle; cut in strips it is used for whips and ropes
- Rb
- a soft silvery metallic element of the alkali metal group; burns in air and reacts violently in water; occurs in carnallite and lepidolite and pollucite
- Re
- a rare heavy polyvalent metallic element that resembles manganese chemically and is used in some alloys; is obtained as a by-product in refining molybdenum
- reactant
- a chemical substance that is present at the start of a chemical reaction
- reagent
- a chemical agent for use in chemical reactions
- reagin
- an immunoglobulin E that is formed as an antibody against allergens (such as pollen); attaches to cell membranes causing the release of histamine and other substances responsible for the local inflammation characteristic of an allergy
- realgar
- a rare soft orange mineral consisting of arsenic sulphide; an important ore of arsenic
- recombinant DNA
- genetically engineered DNA made by recombining fragments of DNA from different organisms
- recombinant protein
- a protein derived from recombinant DNA
- recycling
- used or abandoned materials for use in creating new products
- red clay
- clay whose redness results from iron oxide
- red fire
- combustible material (usually salts of lithium or strontium) that burns bright red; used in flares and fireworks
- red silk cotton
- a plant fiber from the red silk-cotton tree of eastern India; inferior to kapok
- red tide
- seawater that is discolored by large numbers of certain dinoflagellates that produce saxitoxin
- red-lead putty
- a cement resembling putty; made by mixing white and red lead in boiled linseed oil; used as luting on pipe fittings
- reducer
- a substance capable of bringing about the reduction of another substance as it itself is oxidized; used in photography to lessen the density of a negative or print by oxidizing some of the loose silver
- reductase
- an enzyme that catalyses the biochemical reduction of some specified substance
- refrigerant
- any substance used to provide cooling (as in a refrigerator)
- regosol
- a type of soil consisting of unconsolidated material from freshly deposited alluvium or sand
- regur
- a rich black loam of India
- Remicade
- a monoclonal antibody (trade name Remicade) used to treat Crohn's disease and rheumatoid arthritis; administered by infusion; use and dosage must be determined by a physician
- remover
- a solvent that removes a substance (usually from a surface)
- render
- a substance similar to stucco but exclusively applied to masonry walls
- renin
- a proteolytic enzyme secreted by the kidneys; catalyzes the formation of angiotensin and thus affects blood pressure
- rennet
- a substance that curdles milk in making cheese and junket
- rensselaerite
- a kind of soft talc; sometimes used as wood filler
- repellant
- a chemical substance that repels animals
- repellant
- a compound with which fabrics are treated to repel water
- resid
- oil products that remain after petroleum has been distilled
- residual clay
- the soil that is remaining after the soluble elements have been dissolved
- residue
- matter that remains after something has been removed
- resin
- any of a class of solid or semisolid viscous substances obtained either as exudations from certain plants or prepared by polymerization of simple molecules
- resinoid
- a plastic containing resins
- resorcinol
- a crystalline phenol obtained from various resins; used in ointments for acne and in dandruff shampoos
- restrainer
- a chemical that is added to a photographic developer in order to retard development and reduce the amount of fog on a film
- restriction endonuclease
- any of the enzymes that cut nucleic acid at specific restriction sites and produce restriction fragments; obtained from bacteria (where they cripple viral invaders); used in recombinant DNA technology
- resuspension
- a renewed suspension of insoluble particles after they have been precipitated
- retinal purple
- a red photopigment in the retinal rods of vertebrates; dissociates into retinene by light
- retinal
- either of two yellow to red retinal pigments formed from rhodopsin by the action of light
- reverse transcriptase
- a polymerase that catalyzes the formation of DNA using RNA as a template; found especially in retroviruses
- RF
- a substance produced by the hypothalamus that is capable of accelerating the secretion of a given hormone by the anterior pituitary gland
- Rg
- a radioactive transuranic element
- Rh
- a white hard metallic element that is one of the platinum group and is found in platinum ores; used in alloys with platinum
- Rh antibody
- rhesus factor antibody
- Rh factor
- a blood group antigen possessed by Rh-positive people; if an Rh-negative person receives a blood transfusion from an Rh-positive person it can result in hemolysis and anemia
- rheum
- a watery discharge from the mucous membranes (especially from the eyes or nose)
- rhinestone
- an imitation diamond made from rock crystal or glass or paste
- rhodochrosite
- a mineral consisting of manganese carbonate; a source of manganese
- rhodolite
- a red or pink variety of garnet used as a gemstone
- rhodonite
- a pink or red mineral consisting of crystalline manganese silicate; used as an ornamental stone
- rhyolite
- very acid volcanic rock
- ribose
- a pentose sugar important as a component of ribonucleic acid
- rice paper
- a thin delicate material resembling paper; made from the rice-paper tree
- ricin
- a toxic protein extracted from castor beans; used as a chemical reagent; can be used as a bioweapon
- ricinoleic acid
- an oily fatty acid found in castor oil and used in soap
- ridge tile
- a decorative tile that is bent in cross section; used to cover the ridge of a roof
- Ringer's solution
- an aqueous solution containing the chlorides of sodium and potassium and calcium that is isotonic to animal tissues; used to correct dehydration and (in physiological experiments) as a medium for in vitro preparations
- rinse
- a liquid preparation used on wet hair to give it a tint
- Rn
- a radioactive gaseous element formed by the disintegration of radium; the heaviest of the inert gasses; occurs naturally (especially in areas over granite) and is considered a hazard to health
- RNA
- (biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell
- RNA polymerase
- the enzyme that copies DNA into RNA
- RNase
- a transferase that catalyzes the hydrolysis of ribonucleic acid
- road metal
- broken rock used for repairing or making roads
- roan
- a soft sheepskin leather that is colored and finished to resemble morocco; used in bookbinding
- Rochelle salts
- a double salt used in Seidlitz powder; acts as a cathartic
- rock crystal
- a clear quartz used in making electronic and optical equipment
- rock
- material consisting of the aggregate of minerals like those making up the Earth's crust
- rocket fuel
- an explosive charge that propels a rocket
- Rolaids
- an antacid
- roofing material
- building material used in constructing roofs
- roofing paper
- a heavy paper impregnated with tar and used as part of a roof for waterproofing
- roofing tile
- a thin flat slab of fired clay used for roofing
- rose quartz
- a translucent rose-red variety of quartz used for ornaments
- rotenone
- a white crystalline insecticide that has low toxicity for mammals; is used in home gardens; extracted from the roots of derris and cube
- rottenstone
- a weathered and decomposed siliceous limestone; in powdered form it is used in polishing
- roughcast
- a coarse plaster for the surface of external walls
- royal jelly
- a secretion of the pharyngeal glands of bees that is fed to very young larvae and to bees destined to be queens
- Ru
- a rare polyvalent metallic element of the platinum group; it is found associated with platinum
- rubber cement
- an adhesive made by dissolving unvulcanized rubber in a solvent like benzene or naphtha
- rubber
- any of various synthetic elastic materials whose properties resemble natural rubber
- rubbish
- worthless material that is to be disposed of
- rubicelle
- a yellow or orange variety of ruby spinel
- ruby
- a transparent deep red variety of corundum; used as a gemstone and in lasers
- ruby spinel
- a spinel used as a gemstone (usually dark red)
- rudaceous rock
- a sedimentary rock formed of coarse-grained material
- Russia leather
- a smooth leather tanned with willow, birch, or oak, and scented on the flesh side with birch oil
- rust
- a red or brown oxide coating on iron or steel caused by the action of oxygen and moisture
- rust inhibitor
- antioxidant that inhibits the formation of rust
- rutile
- a mineral consisting of titanium dioxide in crystalline form; occurs in metamorphic and plutonic rocks and is a major source of titanium
- S
- an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions)
- sable
- the expensive dark brown fur of the marten
- saccharic acid
- a white dicarboxylic acid formed from oxidation of sugar or starch
- saccharose
- a complex carbohydrate found in many plants and used as a sweetening agent
- saffranine
- any of a class of chiefly red organic dyes
- sago
- powdery starch from certain sago palms; used in Asia as a food thickener and textile stiffener
- sal soda
- a sodium salt of carbonic acid; used in making soap powders and glass and paper
- sal volatile
- a solution of ammonium carbonate in ammonia water and alcohol
- salicylate
- a salt of salicylic acid (included in several commonly used drugs)
- saline
- an isotonic solution of sodium chloride and distilled water
- salmon oil
- a fatty oil obtained from the wastes in canning salmon; used in making soap and dressing leather
- salt
- a compound formed by replacing hydrogen in an acid by a metal (or a radical that acts like a metal)
- samarskite
- a complex black mineral occurring in pegmatites
- sand
- a loose material consisting of grains of rock or coral
- sandstone
- a sedimentary rock consisting of sand consolidated with some cement (clay or quartz etc.)
- sap
- a watery solution of sugars, salts, and minerals that circulates through the vascular system of a plant
- saponin
- any of various plant glucosides that form soapy lathers when mixed and agitated with water; used in detergents and foaming agents and emulsifiers
- sapphire
- a precious transparent stone of rich blue corundum valued as a gemstone
- sapphirine
- a rare light blue or green mineral; consists of aluminum and magnesium silicate and occurs as small grains in some metamorphic rocks
- saprolite
- a deposit of clay and disintegrating rock that is found in its original place
- sapropel
- sludge (rich in organic matter) that accumulates at the bottom of lakes or oceans
- saran
- any of various thermoplastic resins used to make things
- sarcosine
- a sweetish crystalline amino acid
- sard
- a deep orange-red variety of chalcedony
- sardine oil
- oil obtained from sardines and used chiefly as a lubricant and in soap
- sardonyx
- an onyx characterized by parallel layers of sard and a different colored mineral
- saturated fatty acid
- a fatty acid whose carbon chain cannot absorb any more hydrogen atoms; found chiefly in animal fats
- saw log
- log large enough to be sawed into boards
- sawdust
- fine particles of wood made by sawing wood
- saxitoxin
- a powerful neurotoxin produced by certain dinoflagellates found in red tides; it can accumulate in mollusks that feed on the dinoflagellates and cause food poisoning to humans
- Sb
- a metallic element having four allotropic forms; used in a wide variety of alloys; found in stibnite
- Sc
- a white trivalent metallic element; sometimes classified in the rare earth group; occurs in the Scandinavian mineral thortveitite
- scabicide
- a drug that destroys the itch mite that causes scabies
- scavenger
- a chemical agent that is added to a chemical mixture to counteract the effects of impurities
- scheelite
- a mineral used as an ore of tungsten
- schist
- any metamorphic rock that can be split into thin layers
- schorl
- black tourmaline
- scrap iron
- iron to be melted again and reworked
- scrap metal
- discarded metal suitable for reprocessing
- scratch pad
- pad for preliminary or hasty writing or notes or sketches etc
- Se
- a toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite)
- sea coal
- pulverized bituminous coal; used as a foundry facing
- sea spray
- spray from ocean waves
- seal oil
- a pale yellow to red-brown fatty oil obtained from seal blubber; used in making soap and dressing leather and as a lubricant
- seal
- the pelt or fur (especially the underfur) of a seal
- sealant
- a kind of sealing material that is used to form a hard coating on a porous surface (as a coat of paint or varnish used to size a surface)
- sealing material
- any substance used to seal joints or fill cracks in a porous surface
- secretase
- a set of enzymes believed to snip pieces off a longer protein producing fragments of amyloid protein that bunch up and create amyloid protein plaques in brain tissue (the pathological hallmark of Alzheimer's)
- sedimentary clay
- clay soil formed by sedimentary deposits
- sedimentary rock
- rock formed from consolidated clay sediments
- seed lac
- granular material obtained from stick lac by crushing and washing
- Seidlitz powders
- an effervescing salt containing sodium bicarbonate and Rochelle salt and tartaric acid; used as a cathartic
- selenic acid
- a strong acid (H2SeO4) analogous to sulfuric acid
- semiconducting material
- a substance as germanium or silicon whose electrical conductivity is intermediate between that of a metal and an insulator; its conductivity increases with temperature and in the presence of impurities
- Senegal gum
- gum arabic from the vicinity of the Senegal river
- sensitiser
- (chemistry) a substance other than a catalyst that facilitates the start of a catalytic reaction
- sepia
- rich brown pigment prepared from the ink of cuttlefishes
- serine
- a sweetish crystalline amino acid involved in the synthesis by the body of cysteine
- serum albumin
- albumin occurring in blood serum; serves to maintain the somatic pressure of the blood
- serum globulin
- globulins occurring in blood serum and containing most of the antibodies of the blood
- sewage
- waste matter carried away in sewers or drains
- sewer gas
- foul-smelling gas that forms in sewers
- sex hormone
- any hormone affecting the development and growth of sex organs
- Sg
- a transuranic element
- shag
- a strong coarse tobacco that has been shredded
- shake
- building material used as siding or roofing
- shale
- a sedimentary rock formed by the deposition of successive layers of clay
- shale oil
- oil extracted from oil shale by heating
- shark oil
- a fatty yellow to brown oil obtained from the livers of sharks; used for dressing leather and as a source of vitamin A
- sheep dip
- a liquid mixture containing pesticides in which sheep are dipped to kill parasites
- shell
- the material that forms the hard outer covering of many animals
- shellac
- lac purified by heating and filtering; usually in thin orange or yellow flakes but sometimes bleached white
- Shetland wool
- a wool obtained from sheep of the Shetland islands
- shingle
- coarse beach gravel of small waterworn stones and pebbles (or a stretch of shore covered with such gravel)
- shingling
- (geology) sediment in which flat pebbles are uniformly tilted in the same direction
- shoddy
- reclaimed wool fiber
- shoe leather
- leather used to make shoes
- short-staple cotton
- cotton with relatively short fibers
- shot metal
- an alloy that is 98% lead and 2% arsenic; used in making small shot
- Si
- a tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and feldspar and granite and quartz and sand; used as a semiconductor in transistors
- sial
- the granitelike rocks that form the outermost layer of the earth's crust; rich in silicon and aluminum
- siding
- material applied to the outside of a building to make it weatherproof
- sienna
- an earth color containing ferric oxides; used as a pigment
- silex
- a pure form of finely ground silica
- silica gel
- a porous form of silica that is highly absorbent
- silica
- a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite
- silicate
- a salt or ester derived from silicic acid
- silicic acid
- a jellylike substance (hydrated silica)
- silicide
- any of various compounds of silicon with a more electropositive element or radical
- silicon bronze
- a bronze with 2-3% silicon that is resistant to corrosion
- silicon carbide
- an extremely hard blue-black crystalline compound (SiC) used as an abrasive and a heat refractory material; crystals of silicon carbide can be used as semiconductors
- silicone resin
- a polymeric silicone compound
- silicone rubber
- made from silicone elastomers; retains flexibility resilience and tensile strength over a wide temperature range
- silicone
- any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation
- silk
- animal fibers produced by silkworms and other larvae that spin cocoons and by most spiders
- siloxane
- any of a large class of compounds that have alternate silicon and oxygen atoms
- silt
- mud or clay or small rocks deposited by a river or lake
- siltstone
- a fine-grained sandstone of consolidated silt
- silver bromide
- a bromide that darkens when exposed to light; used in making photographic emulsions
- silver chloride
- a chloride used chiefly in the manufacture of photographic emulsions
- silver iodide
- an iodide that is used in photography, in seeding clouds to make rain, and in medicine
- silver nitrate
- a nitrate used in making photographic emulsions; also used in medicine as a cautery and as a topical antibacterial agent
- silver solder
- a solder that contains silver
- silvex
- a herbicide that is effective in controlling woody plants but is toxic to animals
- sima
- rock that form the continuous lower layer of the earth's crust; rich in silicon and magnesium
- simazine
- a herbicide used to control weeds (especially among crops)
- Simoniz
- a brand of car polish
- simple protein
- a protein that yields only amino acids when hydrolyzed
- sinoper
- a red ocher formerly used as a pigment
- sisal
- a plant fiber used for making rope
- size
- any glutinous material used to fill pores in surfaces or to stiffen fabrics
- ski wax
- wax used on the bottom of skis
- slack
- dust consisting of a mixture of small coal fragments and coal dust and dirt that sifts out when coal is passed over a sieve
- slate
- a fine-grained metamorphic rock that can be split into thin layers
- slate
- thin layers of rock used for roofing
- slip
- potter's clay that is thinned and used for coating or decorating ceramics
- slop
- (usually plural) waste water from a kitchen or bathroom or chamber pot that has to be emptied by hand
- SLS
- a caustic detergent useful for removing grease; although commonly included in personal care items (shampoos and toothpastes etc.) it can irritate skin and should not be swallowed
- sludge
- the precipitate produced by sewage treatment
- slurry
- a suspension of insoluble particles (as plaster of Paris or lime or clay etc.) usually in water
- slush
- partially melted snow
- Sm
- a grey lustrous metallic element of the rare earth group; is used in special alloys; occurs in monazite and bastnasite
- smaltite
- a grey mineral consisting of cobalt arsenide and nickel; an important source of cobalt and nickel
- smelling salts
- a pungent preparation of ammonium carbonate and perfume; sniffed as a stimulant to relieve faintness
- Sn
- a silvery malleable metallic element that resists corrosion; used in many alloys and to coat other metals to prevent corrosion; obtained chiefly from cassiterite where it occurs as tin oxide
- snake oil
- (medicine) any of various liquids sold as medicine (as by a travelling medicine show) but medically worthless
- snake venom
- venom secreted by certain snakes
- snow
- a layer of snowflakes (white crystals of frozen water) covering the ground
- snuff
- the charred portion of a candlewick
- soaprock
- a soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments
- SOD
- an enzyme that catalyzes the conversion of superoxide into hydrogen peroxide and oxygen
- soda lime
- a mixture of sodium and calcium hydroxides; absorbs liquids and gases
- soda niter
- (NaNO3) used especially as a fertilizer and explosive
- sodalite
- a vitreous mineral consisting of sodium aluminum silicate and sodium chloride in crystalline form; occurs in igneous rocks
- sodium bichromate
- a red-orange salt used as a mordant
- sodium carboxymethyl cellulose
- a gummy substance that is a sodium salt of carboxymethyl cellulose; used as a thickening or emulsifying agent
- sodium chlorate
- a colorless salt (NaClO3) used as a weed killer and an antiseptic
- sodium cyanide
- a white poisonous salt (NaCN) used in electroplating
- sodium fluoride
- a colorless crystalline salt of sodium (NaF) used in fluoridation of water and to prevent tooth decay
- sodium hydride
- a flammable grey crystalline binary compound (NaH)
- sodium hypochlorite
- an unstable salt (NaOCl) used as a bleaching agent and disinfectant
- sodium iodide
- a crystalline salt used like potassium iodide
- sodium nitrite
- nitrite used to preserve and color food especially in meat and fish products; implicated in the formation of suspected carcinogens
- sodium orthophosphate
- phosphate of sodium; used as a laxative to cleanse the bowels
- sodium pyrophosphate
- a sodium salt of pyrophosphoric acid used as a builder in soaps and detergents
- sodium silicate
- a viscous glass consisting of sodium silicate in solution; used as a cement or as a protective coating and to preserve eggs
- sodium sulfate
- a solid white bitter salt used in manufacturing glass and paper and dyes and pharmaceuticals
- sodium tripolyphosphate
- a sodium salt of triphosphoric acid used as a builder in soaps and detergents
- soft glass
- glass having a relatively low softening point
- soft solder
- solder that melts at a relatively low temperature
- soft water
- water that is not hard (does not contain mineral salts that interfere with the formation of lather with soap)
- softener
- a substance added to another to make it less hard
- soil conditioner
- a chemical substance used to improve the structure of the soil and increase its porosity
- solder
- an alloy (usually of lead and tin) used when melted to join two metal surfaces
- soldering flux
- flux applied to surfaces that are to be joined by soldering; flux cleans the surfaces and results in a better bond
- solid
- matter that is solid at room temperature and pressure
- solute
- the dissolved matter in a solution; the component of a solution that changes its state
- solution
- a homogeneous mixture of two or more substances; frequently (but not necessarily) a liquid solution
- solvate
- a compound formed by solvation (the combination of solvent molecules with molecules or ions of the solute)
- solvating agent
- an agent that converts something into a solvate
- Sonora lac
- resembling lac; secreted by a scale living on twigs of certain Mexican shrubs; used locally as medicine
- sorbate
- a material that has been or is capable of being taken up by another substance by either absorption or adsorption
- sorbent
- a material that sorbs another substance; i.e. that has the capacity or tendency to take it up by either absorption or adsorption
- sorbic acid
- a white crystalline carboxylic acid used as a preservative
- soup
- any composition having a consistency suggestive of soup
- sour mash
- a mash with optimum acidity for yeast fermentation; a mixture of old and new mash; used in distilling some whiskeys
- sourdough
- a leaven of dough in which fermentation is active; used by pioneers for making bread
- spackle
- powder (containing gypsum plaster and glue) that when mixed with water forms a plastic paste used to fill cracks and holes in plaster
- spar
- any of various nonmetallic minerals (calcite or feldspar) that are light in color and transparent or translucent and cleavable
- sparkle metal
- matte that has 74 percent copper
- spelter
- impure zinc containing about three percent lead and other impurities (especially in the form of ingots)
- sperm oil
- an animal oil found in the blubber of the sperm whale
- spermaceti
- a white waxy substance from oil of the sperm whale
- spice
- aromatic substances of vegetable origin used as a preservative
- spiegel
- pig iron containing manganese; used as a deoxidizing agent and to raise the manganese content in making steel
- spill
- liquid that is spilled
- spindrift
- spray blown up from the surface of the sea
- spinel
- a hard glassy mineral consisting of an oxide of magnesium and aluminum; occurs in various colors that are used as gemstones
- spirit gum
- an adhesive solution made of gum and ether and used to attach false hair to skin
- spirits of wine
- rectified ethyl alcohol
- spodumene
- a pyroxene mineral consisting of lithium aluminum silicate; a source of lithium
- sponge
- a porous mass of interlacing fibers that forms the internal skeleton of various marine animals and usable to absorb water or any porous rubber or cellulose product similarly used
- spray
- water in small drops in the atmosphere; blown from waves or thrown up by a waterfall
- spray
- a pesticide in suspension or solution; intended for spraying
- squirrel
- the fur of a squirrel
- Sr
- a soft silver-white or yellowish metallic element of the alkali metal group; turns yellow in air; occurs in celestite and strontianite
- stabilizer
- a chemical that is added to a solution or mixture or suspension to maintain it in a stable or unchanging state
- stachyose
- a tetrasaccharide found in the tubers of the Chinese artichoke
- stacte
- (Old Testament) one of several sweet-smelling spices used in incense
- staff
- building material consisting of plaster and hair; used to cover external surfaces of temporary structure (as at an exposition) or for decoration
- stain
- (microscopy) a dye or other coloring material that is used in microscopy to make structures visible
- stained glass
- glass that has been colored in some way; used for church windows
- stand oil
- a thick oil comprised of linseed, tung, or soya oils which have been heated to over 300 C
- stannic chloride
- a colorless caustic liquid made by treating tin with chlorine
- stannite
- a dark grey mineral with a metallic luster that is a source of tin
- stannous fluoride
- a white powder that is used to fluoridate toothpaste
- staphylococcal enterotoxin
- a soluble exotoxin produced by some strains of staphylococcus; a cause of food poisoning
- staphylococcal enterotoxin B
- a form of staphylococcal enterotoxin that has been used as an incapacitating agent in biological warfare
- staple
- a natural fiber (raw cotton, wool, hemp, flax) that can be twisted to form yarn
- star sapphire
- a sapphire that when cut shows a starlike figure in reflected light because of its crystalline structure
- starch
- a commercial preparation of starch that is used to stiffen textile fabrics in laundering
- starting buffer
- buffer solution at the start of a reaction
- steam
- water at boiling temperature diffused in the atmosphere
- steam coal
- coal suitable for use under steam boilers
- stearin
- an ester of glycerol and stearic acid
- steel
- an alloy of iron with small amounts of carbon; widely used in construction; mechanical properties can be varied over a wide range
- steel wool
- a mass of woven steel fibers used as an abrasive
- Stellite
- a very hard alloy of cobalt and chromium with cobalt as the principal ingredient; used to make cutting tools and for surfaces subject to heavy wear
- stercobilinogen
- a chromogen formed in the intestine from the breakdown of bilirubin; yields urobilins on oxidation; some is excreted in the feces and some is resorbed and excreted in bile or urine
- sterling silver
- a silver alloy with no more than 7.5% copper
- sternutator
- a chemical substance that causes sneezing and coughing and crying
- steroid
- any of several fat-soluble organic compounds having as a basis 17 carbon atoms in four rings; many have important physiological effects
- steroid alcohol
- any of a group of natural steroid alcohols derived from plants or animals; they are waxy insoluble substances
- stibnite
- a soft grey mineral; the chief ore of antimony
- stick lac
- lac in its natural state as scraped off twigs and dried
- sticks and stone
- a general term for building materials
- sticky end
- an end of DNA in which one strand of the double helix extends a few units beyond the other
- stiffener
- material used for stiffening something
- straw
- plant fiber used e.g. for making baskets and hats or as fodder
- strawboard
- a coarse yellow cardboard made of straw pulp
- streptodornase
- an enzyme produced by some hemolytic strains of streptococcus that dissolves fibrinous secretions from infections; used medicinally (often in combination with streptokinase)
- streptokinase
- an enzyme produced by some strains of streptococcus that can liquefy blood clots by converting plasminogen to plasmin; used medicinally in some cases of myocardial infarction and pulmonary embolism
- streptolysin
- any of several hemolysins derived from strains of streptococcus
- string
- a tough piece of fiber in vegetables, meat, or other food (especially the tough fibers connecting the two halves of a bean pod)
- stripper
- a chemical compound used to remove paint or varnish
- strontianite
- a mineral consisting of strontium carbonate
- strontium 90
- a radioactive isotope of strontium (with the mass number 90) that is present in the fallout from nuclear explosions; can be assimilated like calcium into bones
- strophanthin
- a bitter and very toxic glycoside derived from plants of the genus Strophanthus; in moderate doses it is a cardiac stimulant but in larger doses it is a powerful poison; used in Africa as an arrow poison
- structural iron
- iron that has been cast or worked in structural shapes
- structural steel
- a strong steel that is rolled into shapes that are used in construction
- strychnine
- an alkaloid plant toxin extracted chiefly from nux vomica; formerly used as a stimulant
- stucco
- a plaster now made mostly from Portland cement and sand and lime; applied while soft to cover exterior walls or surfaces
- Styrofoam
- a light resilient foam of polystyrene
- sublimate
- the product of vaporization of a solid
- subsoil
- the layer of soil between the topsoil and bedrock
- substance
- material of a particular kind or constitution
- substrate
- the substance that is acted upon by an enzyme or ferment
- succinic acid
- a dicarboxylic acid (C4H6O4) active in metabolic processes
- suede
- leather with a napped surface
- sulfanilic acid
- a crystalline acid made from aniline and used as a dye
- sulfate
- a salt or ester of sulphuric acid
- sulfide
- a compound of sulphur and some other element that is more electropositive
- sulfonate
- a salt of sulphonic acid
- sulfonic acid
- an acid derived from sulphuric acid
- sulfur dioxide
- a colorless toxic gas (SO2) that occurs in the gases from volcanoes; used in many manufacturing processes and present in industrial emissions; causes acid rain
- sulfur hexafluoride
- a colorless gas that is soluble in alcohol and ether; a powerful greenhouse gas widely used in the electrical utility industry
- sulfur oxide
- any of several oxides of sulphur
- superoxide
- a metallic oxide containing the univalent anion O2-
- superoxide
- the univalent anion O2-
- surface soil
- the layer of soil on the surface
- surface-active agent
- a chemical agent capable of reducing the surface tension of a liquid in which it is dissolved
- surgical spirit
- methylated spirit used in the practice of medicine (especially for cleansing the skin before injections or before surgery)
- suspension
- a mixture in which fine particles are suspended in a fluid where they are supported by buoyancy
- Swedish iron
- wrought iron of high purity made in Sweden
- swinging chad
- a chad that is incompletely removed and still attached at two corners
- sylvine
- a mineral consisting of native potassium chloride; an important ore of potassium that is found in sedimentary beds
- synthetic resin
- a resin having a polymeric structure; especially a resin in the raw state; used chiefly in plastics
- synthetic
- a compound made artificially by chemical reactions
- system
- (physical chemistry) a sample of matter in which substances in different phases are in equilibrium
- T
- one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
- T
- a base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine
- Ta
- a hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite
- tachylite
- a basic or basalt glass
- taconite
- a variety of chert containing magnetite and hematite; mined as a low-grade iron ore
- talc
- a fine grained mineral having a soft soapy feel and consisting of hydrated magnesium silicate; used in a variety of products including talcum powder
- tall oil
- an oil derived from wood pulp and used in making soaps or lubricants
- tallow
- obtained from suet and used in making soap, candles and lubricants
- tallow oil
- an animal oil obtained by pressing tallow; used as a lubricant
- tambac
- an alloy of copper and zinc (and sometimes arsenic) used to imitate gold in cheap jewelry and for gilding
- tannic acid
- any of various complex phenolic substances of plant origin; used in tanning and in medicine
- tantalite
- a mineral consisting of tantalum oxide of iron and manganese that occurs with niobite or in coarse granite; an ore of tantalum
- tarmac
- a paving material of tar and broken stone; mixed in a factory and shaped during paving
- tartaric acid
- an acid found in many fruits; used in soft drinks and confectionery and baking powder
- tartrate
- a salt or ester of tartaric acid
- taurine
- a colorless crystalline substance obtained from the bile of mammals
- Tb
- a metallic element of the rare earth group; used in lasers; occurs in apatite and monazite and xenotime and ytterbite
- Tc
- a crystalline metallic element not found in nature; occurs as one of the fission products of uranium
- TCE
- a heavy colorless highly toxic liquid used as a solvent to clean electronic components and for dry cleaning and as a fumigant; causes cancer and liver and lung damage
- Te
- a brittle silver-white metalloid element that is related to selenium and sulfur; it is used in alloys and as a semiconductor; occurs mainly as tellurides in ores of copper and nickel and silver and gold
- Teflon
- a material used to coat cooking utensils and in industrial applications where sticking is to be avoided
- tektite
- thought to derive from meteorites
- telluride
- any binary compound of tellurium with other more electropositive elements
- telomerase
- an enzyme in eukaryotic cells that can add telomeres to the ends of chromosomes after they divide
- tenderiser
- a substance (as the plant enzyme papain) applied to meat to make it tender
- terbium metal
- a separate group of related lanthanides, including terbium, europium, gadolinium, and sometimes dysprosium
- terpene
- an unsaturated hydrocarbon obtained from plants
- terra alba
- finely pulverized gypsum used especially as a pigment
- testosterone
- a potent androgenic hormone produced chiefly by the testes; responsible for the development of male secondary sex characteristics
- tetanus antitoxin
- antitoxin given for short-term immunization against tetanus in cases of possible exposure to the tetanus bacillus
- tetanus immune globulin
- sterile solution of globulins derived from the blood plasma of a person who has been immunized for tetanus; provides short-term immunization against tetanus in cases of possible exposure to the tetanus bacillus
- tetrabasic acid
- an acid containing four replaceable hydrogen atoms per molecule
- tetrachloride
- any compound that contains four chlorine atoms per molecule
- tetrafluoroethylene
- a flammable gaseous fluorocarbon used in making plastics (polytetrafluoroethylene resins)
- tetrahalide
- any halide containing four halogen atoms in its molecules
- tetrasaccharide
- any of a variety of carbohydrates that yield four monosaccharide molecules on complete hydrolysis
- tetrodotoxin
- a powerful neurotoxin found in the ovaries of pufferfish
- tetrose
- any monosaccharide sugar containing four atoms of carbon per molecule
- tetroxide
- an oxide containing four atoms of oxygen in the molecule
- Th
- a soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands
- thatch
- plant stalks used as roofing material
- thermoplastic
- a material that softens when heated and hardens again when cooled
- thermosetting compositions
- a material that hardens when heated and cannot be remolded
- thiazine
- a compound made up of a ring of four carbon atoms and one sulfur atom and one nitrogen atom
- thickener
- any material used to thicken
- thiocyanate
- a salt of thiocyanic acid; formed when alkaline cyanides are fused with sulfur
- thiocyanic acid
- an unstable acid that can be obtained by distilling a thiocyanate salt
- thiouracil
- depresses the function of the thyroid gland
- thorite
- a radioactive mineral consisting of thorium silicate; it is a source of thorium that is found in coarse granite
- thortveitite
- a mineral consisting of scandium yttrium silicate; a source of scandium
- threonine
- a colorless crystalline amino acid found in protein; occurs in the hydrolysates of certain proteins; an essential component of human nutrition
- thrombin
- an enzyme that acts on fibrinogen in blood causing it to clot
- thyme camphor
- a colorless crystalline solid used in perfume or preserving biological specimens or in embalming or medically as a fungicide or antiseptic
- thyroglobulin
- an iodine containing protein that is obtained from the thyroid gland and exhibits the general properties of the globulins
- thyronine
- a phenolic amino acid of which thyroxine is a derivative
- thyroprotein
- a preparation made from iodinated protein and having an action similar to thyroxine
- Ti
- a light strong grey lustrous corrosion-resistant metallic element used in strong lightweight alloys (as for airplane parts); the main sources are rutile and ilmenite
- ticker tape
- a continuous thin ribbon of paper on which stock quotes are written
- Tiffany glass
- a kind of opalescent colored glass that was used in the early 1900s for stained-glass windows and lamps
- tincture
- a substance that colors or dyes
- tissue
- a soft thin (usually translucent) paper
- titania
- a white powder used as a pigment for its high covering power and durability
- titanic acid
- a white weak acid that is a hydrated form of titanium dioxide
- Tl
- a soft grey malleable metallic element that resembles tin but discolors on exposure to air; it is highly toxic and is used in rodent and insect poisons; occurs in zinc blende and some iron ores
- Tm
- a soft silvery metallic element of the rare earth group; isotope 170 emits X-rays and is used in small portable X-ray machines; it occurs in monazite and apatite and xenotime
- TNF
- a proinflammatory cytokine that is produced by white blood cells (monocytes and macrophages); has an antineoplastic effect but causes inflammation (as in rheumatoid arthritis)
- toilet roll
- a roll of toilet paper
- toluic acid
- an isomeric acid derived from toluene
- toner
- a black or colored powder used in a printer to develop a xerographic image
- toner
- a solution containing chemicals that can change the color of a photographic print
- tool steel
- alloy steel that is suitable for making tools; is hard and tough and can retain a cutting edge
- top fermenting yeast
- brewer's yeast used in top fermentation of ale
- topaz
- a mineral (fluosilicate of aluminum) that occurs in crystals of various colors and is used as a gemstone
- tortoiseshell
- the mottled horny substance of the shell of some turtles
- tourmaline
- a mineral that is a complex borosilicate and hydroxide of aluminum containing iron and magnesium and calcium and lithium and sodium; it is usually black but occurs in transparent colored forms that are used as gemstones
- town gas
- coal gas manufactured for domestic and industrial use
- toxic industrial waste
- poisonous waste materials; can cause injury (especially by chemical means)
- toxin
- a poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species
- toxin antitoxin
- a mixture of toxin and antitoxin used to immunize against a disease
- trace element
- an element that occurs at very small quantities in the body but is nonetheless important for many biological processes
- tracing paper
- a semitransparent paper that is used for tracing drawings
- tragacanth
- a gum used in pharmacy, adhesives, and textile printing
- train oil
- a white to brown oil obtained from whale blubber; formerly used as an illuminant
- trans fatty acid
- a fatty acid that has been produced by hydrogenating an unsaturated fatty acid (and so changing its shape); found in processed foods such as margarine and fried foods and puddings and commercially baked goods and partially hydrogenated vegetable oils
- transactinide
- any of the artificially produced elements with atomic numbers greater than 103
- transfer paper
- a paper that is coated with a preparation for transferring a design to another surface
- transferase
- any of various enzymes that move a chemical group from one compound to another compound
- translucent substance
- a material having the property of admitting light diffusely; a partly transparent material
- transparent gem
- a gemstone having the property of transmitting light without serious diffusion
- transudate
- a substance that transudes
- transuranic element
- any element having an atomic number greater than 92 (which is the atomic number of uranium); all are radioactive
- tremolite
- a white or pale green mineral (calcium magnesium silicate) of the amphibole group used as a form of asbestos
- TRH
- hormone released by the hypothalamus that controls the release of thyroid-stimulating hormone from the anterior pituitary
- tri-chad
- a chad that is incompletely removed and still attached at three corners
- tri-iodothyronine
- thyronine with three iodine atoms added
- triazine
- any of three isomeric compounds having three carbon and three nitrogen atoms in a six-membered ring
- tribasic acid
- an acid containing three replaceable hydrogen atoms per molecule
- tribasic sodium phosphate
- the tertiary phosphate of sodium used as a builder in soaps and detergents
- tributyrin
- a bitter oily triglyceride of butyric acid; a form of butyrin
- trichloracetic acid
- a strong acid made by chlorinating acetic acid
- trichloride
- any compound containing three chlorine atoms in each molecule
- tridymite
- a mineral form of silica
- triglyceride
- glyceride occurring naturally in animal and vegetable tissues; it consists of three individual fatty acids bound together in a single large molecule; an important energy source forming much of the fat stored by the body
- trimer
- a polymer (or a molecule of a polymer) consisting of three identical monomers
- triose
- any monosaccharide sugar containing three atoms of carbon per molecule
- trioxide
- an oxide containing three atoms of oxygen in the molecule
- triphosphopyridine
- a pyridine ring with three phosphorus groups
- triphosphopyridine nucleotide
- a coenzyme of several enzymes
- triphosphoric acid
- an acid that is a partial anhydride of three molecules of phosphoric acid; known chiefly in the form of its salts and esters
- trisaccharide
- any of a variety of carbohydrates that yield three monosaccharide molecules on complete hydrolysis
- tritium
- a radioactive isotope of hydrogen; atoms of tritium have three times the mass of ordinary hydrogen atoms
- trypsin
- an enzyme of pancreatic origin; catalyzes the hydrolysis of proteins to smaller polypeptide units
- trypsinogen
- inactive precursor of trypsin; a substance secreted by the pancreas and converted to active trypsin by enterokinase in the small intestine
- tryptophan
- an amino acid that occurs in proteins; is essential for growth and normal metabolism; a precursor of niacin
- TSH
- anterior pituitary hormone that stimulates the function of the thyroid gland
- tuberculin
- a sterile liquid containing a purified protein derivative of the tuberculosis bacterium; used in the diagnosis of tuberculosis
- tufa
- hard volcanic rock composed of compacted volcanic ash
- Tums
- an antacid
- tuna oil
- an oil obtained from tuna
- tundra soil
- a black mucky soil with a frozen subsoil that is characteristic of Arctic and subarctic regions
- tungstate
- a salt of tungstic acid
- tungsten steel
- a very hard heat-resistant steel containing tungsten
- tungstic acid
- an oxyacid of tungsten (often polymeric in nature) formed by neutralizing alkaline tungstate solutions
- Turkish tobacco
- a dark aromatic tobacco of eastern Europe that is used in cigarettes
- turquoise
- a blue to grey green mineral consisting of copper aluminum phosphate
- twins
- (mineralogy) two interwoven crystals that are mirror images on each other
- type metal
- an alloy of tin and lead and antimony used to make printing type
- typewriter paper
- writing paper suitable for use in a typewriter
- tyramine
- amino acid derived from tyrosine; has a sympathomimetic action; found in chocolate and cola drinks and ripe cheese and beer
- Tyrian purple
- a red-purple to deep purple dye obtained from snails or made synthetically
- tyrosine
- an amino acid found in most proteins; a precursor of several hormones
- U
- a base containing nitrogen that is found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine
- U
- a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons
- U308
- an impure mixture of uranium oxides obtained during the processing of uranium ore
- ultramarine
- blue pigment made of powdered lapis lazuli
- umber
- an earth pigment
- undecylenic acid
- an acid that is a component of perspiration
- undercut
- the material removed by a cut made underneath
- unleaded gasoline
- gasoline that has not been treated with a lead compound
- Unq
- a radioactive transuranic element which has been synthesized
- unsaturated fatty acid
- a fatty acid whose carbon chain can absorb additional hydrogen atoms
- uranium 235
- a uranium isotope with mass number 235; capable of sustaining chain reactions
- uranium 238
- the commonest isotope of uranium; it is not fissionable but when irradiated with neutrons it produces fissionable plutonium 239
- uranium ore
- any ore from which uranium can be extracted
- uranyl nitrate
- a yellow salt obtained by the reaction of uranium salts with nitric acid
- uranyl oxalate
- a salt obtained by the reaction of uranium salts with oxalic acid
- uranyl
- the bivalent radical UO2 which forms salts with acids
- urate
- a salt of uric acid
- urea-formaldehyde resin
- a clear thermosetting resin made from urea and formaldehyde and used in electrical fittings, adhesives, and finishes
- urease
- an enzyme that catalyzes the hydrolysis of urea into carbon dioxide and ammonia; is present in intestinal bacteria
- urethane
- an ester of carbamic acid
- uric acid
- a white tasteless odorless crystalline product of protein metabolism; found in the blood and urine
- urobilin
- brown bile pigment formed from urobilinogens and found in feces and in small amounts in urine
- Uub
- a radioactive transuranic element
- Uuh
- a radioactive transuranic element
- Uup
- a radioactive transuranic element
- Uuq
- a radioactive transuranic element
- Uut
- a radioactive transuranic element
- V
- a soft silvery white toxic metallic element used in steel alloys; it occurs in several complex minerals including carnotite and vanadinite
- vaginal discharge
- discharge of secretions from the cervical glands of the vagina; normally clear or white
- valine
- an essential amino acid found in proteins; important for growth in children and nitrogen balance in adults
- vanadate
- a salt or ester of vanadic acid; an anion containing pentavalent vanadium
- vanadic acid
- any of various oxyacids of vanadium; known mostly in the form of its salts
- vanadinite
- a mineral consisting of chloride and vanadate of lead; a source of vanadium
- vanadium steel
- steel alloyed with vanadium for greater strength and high-temperature stability
- vapor
- a visible suspension in the air of particles of some substance
- vat color
- a water-insoluble dye that is applied by reducing the dye to an alkaline form, applying the dye, then regenerating the insoluble dye by oxidation in the material; used for dyeing cotton
- vegetable matter
- matter produced by plants or growing in the manner of a plant
- vegetable tallow
- a waxy fat obtained from certain plants (e.g. bayberry) and used as tallow
- vegetable wax
- a waxy substance obtained from plants (especially from the trunks of certain palms)
- vehicle
- any substance that facilitates the use of a drug or pigment or other material that is mixed with it
- vellum
- a heavy creamy-colored paper resembling parchment
- vellum
- fine parchment prepared from the skin of a young animal e.g. a calf or lamb
- venom
- toxin secreted by animals; secreted by certain snakes and poisonous insects (e.g., spiders and scorpions)
- verd antique
- a dark green impure marble
- vermiculite
- any of a group of yellow or brown hydrous silicate minerals having a micaceous structure
- vernix
- a white cheeselike protective material that covers the skin of a fetus
- vesicant
- a chemical agent that causes blistering (especially mustard gas)
- vicuna
- the wool of the vicuna
- vinegar
- dilute acetic acid
- vinyl
- shiny and tough and flexible plastic; used especially for floor coverings
- vinyl
- a univalent chemical radical derived from ethylene
- Vinylite
- any of various vinyl resins
- virgin wool
- wool not used before; wool not processed or woven before
- viricide
- an agent (physical or chemical) that inactivates or destroys viruses
- vitamin
- any of a group of organic substances essential in small quantities to normal metabolism
- vitamin A
- any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
- vitamin A1
- an unsaturated alcohol that occurs in marine fish-liver oils and is synthesized biologically from carotene
- vitamin A2
- a viscous alcohol that is less active in mammals than is vitamin A1
- vitamin B1
- a B vitamin that prevents beriberi; maintains appetite and growth
- vitamin B12
- a B vitamin that is used to treat pernicious anemia
- vitamin B2
- a B vitamin that prevents skin lesions and weight loss
- vitamin B6
- a B vitamin that is essential for metabolism of amino acids and starch
- vitamin Bc
- a B vitamin that is essential for cell growth and reproduction
- vitamin C
- a vitamin found in fresh fruits (especially citrus fruits) and vegetables; prevents scurvy
- vitamin D
- a fat-soluble vitamin that prevents rickets
- vitamin E
- a fat-soluble vitamin that is essential for normal reproduction; an important antioxidant that neutralizes free radicals in the body
- vitamin H
- a B vitamin that aids in body growth
- vitamin K
- a fat-soluble vitamin that helps in the clotting of blood
- vitamin K1
- a form of vitamin K
- vitamin K3
- a form of vitamin K
- vitamin P
- a vitamin that maintains the resistance of cell and capillary walls to permeation
- vitrification
- a vitrified substance; the glassy result of being vitrified
- VLDL
- large lipoproteins rich in triglycerides; VLDLs circulate through the blood giving up their triglycerides to fat and muscle tissue until the VLDL remnants are modified and converted into LDL
- volatile
- a volatile substance; a substance that changes readily from solid or liquid to a vapor
- volcanic glass
- a kind of natural glass produced when molten lava cools very rapidly
- volcanic rock
- extrusive igneous rock solidified near or on the surface of the Earth
- VX gas
- a highly lethal nerve agent used in chemical warfare; a toxic liquid that penetrates the skin or lungs to disrupt the nervous system and stop respiration; in combat VX gas is deployed by detonating a container over the target area and can persist in the environment up to several weeks after release
- W
- a heavy grey-white metallic element; the pure form is used mainly in electrical applications; it is found in several ores including wolframite and scheelite
- wad
- a small mass of soft material
- wafer
- a small adhesive disk of paste; used to seal letters
- wallpaper
- a decorative paper for the walls of rooms
- wash leather
- piece of chamois used for cleaning and polishing
- waste paper
- paper discarded after use
- waste
- any materials unused and rejected as worthless or unwanted
- water
- once thought to be one of four elements composing the universe (Empedocles)
- water gas
- a mixture of hydrogen and carbon monoxide with small amounts of other gases; made by blowing steam over hot coke or coal
- water of crystallisation
- the water present in hydrated compounds
- water sapphire
- a deep blue cordierite often used as a gemstone
- water softener
- a substance (such as sodium chloride) that lessens the hardness of water by replacing calcium and magnesium ions with sodium ions and so gives the water more efficient sudsing power
- water vapor
- water in a vaporous form diffused in the atmosphere but below boiling temperature
- water-soluble vitamin
- any vitamin that is soluble in water
- watercolor
- water-soluble pigment
- wattle and daub
- building material consisting of interwoven rods and twigs covered with clay
- wax
- any of various substances of either mineral origin or plant or animal origin; they are solid at normal temperatures and insoluble in water
- wax paper
- paper that has been waterproofed by treatment with wax or paraffin
- weapons plutonium
- plutonium 239 that is recovered when nuclear weapons are disassembled; it is stored in plutonium pits
- whit leather
- a leather that has been treated with alum and/or salt
- white gold
- a pale alloy of gold usually with platinum or nickel or palladium
- white vitriol
- a colorless water-soluble powder; used as a mordant or to preserve wood or for the electrodeposition of zinc
- wicker
- slender flexible branches or twigs (especially of willow or some canes); used for wickerwork
- wiesenboden
- a dark meadow soil rich in organic material; developed through poor drainage in humid grassy or sedge regions
- Windsor green
- a light chrome green pigment
- wire glass
- a glass that contains a layer of wire netting in it
- woad
- a blue dyestuff obtained from the woad plant
- wollastonite
- a white or greyish mineral typically found in metamorphic limestone; a silicate of calcium
- wood
- the hard fibrous lignified substance under the bark of trees
- wood pulp
- wood that has been ground to a pulp; used in making cellulose products (as rayon or paper)
- wood sugar
- a sugar extracted from wood or straw; used in foods for diabetics
- wood tar
- any tar obtained by the destructive distillation of wood
- Wood's metal
- a fusible alloy that is half bismuth plus lead, tin, and cadmium; melts at about 160 degrees Fahrenheit
- wool
- fiber sheared from animals (such as sheep) and twisted into yarn for weaving
- wool oil
- any oil used to oil wool before spinning
- wormcast
- cylindrical mass of earth voided by a burrowing earthworm or lugworm
- wove paper
- writing paper having a very faint mesh pattern
- wrapping paper
- a tough paper used for wrapping
- writing ink
- any permanent or washable ink used with pens
- writing paper
- paper material made into thin sheets that are sized to take ink; used for writing correspondence and manuscripts
- wrought iron
- iron having a low carbon content that is tough and malleable and so can be forged and welded
- wulfenite
- a yellow to orange or brown mineral used as a molybdenum ore
- wurtzite
- a brownish-black mineral consisting of zinc sulfide
- xanthate
- a salt or ester of xanthic acid
- xanthic acid
- any of a class of unstable organic acids containing sulphur
- xanthine
- crystalline oxidation product of the metabolism of nucleoproteins; precursor of uric acid; found in many organs and in urine
- Xe
- a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts
- xenotime
- a brown-to-yellow mineral that is a phosphate of yttrium in crystalline form
- xylene
- a colorless flammable volatile liquid hydrocarbon used as a solvent
- Y
- a silvery metallic element that is common in rare-earth minerals; used in magnesium and aluminum alloys
- Yb
- a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime
- yellow ocher
- pigment consisting of a limonite mixed with clay and silica
- ylem
- (cosmology) the original matter that (according to the big bang theory) existed before the formation of the chemical elements
- Yule log
- large log traditionally burned at Christmas
- Zanzibar copal
- a hard copal derived from an African tree
- zeaxanthin
- yellow carotenoid (isomeric with lutein and occurs widely with it) that is the main pigment in yellow Indian corn
- zeolite
- any of a family of glassy minerals analogous to feldspar containing hydrated aluminum silicates of calcium or sodium or potassium; formed in cavities in lava flows and in plutonic rocks
- zinc cadmium sulfide
- cadmium sulfide containing zinc
- zinc sulfide
- a yellow to white crystalline fluorescent compound that occurs naturally as sphalerite or wurtzite and is used as a luminous pigment
- zinkenite
- a steel grey metallic mineral (a sulphide of lead and antimony)
- zinnwaldite
- a mica containing iron and lithium
- zircon
- a common mineral occurring in small crystals; chief source of zirconium; used as a refractory when opaque and as a gem when transparent
- zirconia
- a white crystalline oxide; used in refractories and in insulation and abrasives and enamels and glazes
- Zn
- a bluish-white lustrous metallic element; brittle at ordinary temperatures but malleable when heated; used in a wide variety of alloys and in galvanizing iron; it occurs naturally as zinc sulphide in zinc blende
- Zr
- a lustrous grey strong metallic element resembling titanium; it is used in nuclear reactors as a neutron absorber; it occurs in baddeleyite but is obtained chiefly from zircon
- zymase
- a complex of enzymes that cause glycolysis; originally found in yeast but also present in higher organisms