Nouns denoting natural objects (not man-made)

source
anything (a person or animal or plant or substance) in which an infectious agent normally lives and multiplies
 
berm
a narrow ledge or shelf typically at the top or bottom of a slope
 
Cancer
a small zodiacal constellation in the northern hemisphere; between Leo and Gemini
 
Alpha Centauri
brightest star in Centaurus; second nearest star to the sun
 
Sierra Nevada
a mountain range in southern Spain along the Mediterranean coast to the east of Granada
 
Arno River
a river in central Italy rising in the Apennines and flowing through Florence and Pisa to the Ligurian Sea
 
slope
an elevated geological formation
 
Mount Adams
a mountain peak in southwestern Washington in the Cascade Range (12,307 feet high)
 
oxbow
a U-shaped curve in a stream
 
planet
(astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction
 
sea
a division of an ocean or a large body of salt water partially enclosed by land
 
Coosa River
river that rises in northwestern Georgia and flows southwest through eastern Alabama to join the Tallapoosa River near Montgomery and form the Alabama River
 
Pillars of Hercules
the two promontories at the eastern end of the Strait of Gibraltar; according to legend they were formed by Hercules
 
envelope
a natural covering (as by a fluid)
 
East China Sea
part of the Pacific Ocean near eastern Asia
 
cirrus cloud
a wispy white cloud (usually of fine ice crystals) at a high altitude (4 to 8 miles)
 
Microscopium
a faint constellation in the southern hemisphere near Sagittarius and Capricornus
 
bluff
a high steep bank (usually formed by river erosion)
 
salt plain
a flat expanse of salt left by the evaporation of a body of salt water
 
Columba
a constellation in the southern hemisphere near Puppis and Caelum
 
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