Nouns denoting natural objects (not man-made)

polder
low-lying land that has been reclaimed and is protected by dikes (especially in the Netherlands)
 
catch
anything that is caught (especially if it is worth catching)
 
collector
a crater that has collected cosmic material hitting the earth
 
comet
(astronomy) a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit
 
unit cell
the smallest group of atoms or molecules whose repetition at regular intervals in three dimensions produces the lattices of a crystal
 
Cape York
the northern tip of Cape York Peninsula at the Torres Strait; the northernmost point of the Australian mainland
 
ridge
a long narrow natural elevation on the floor of the ocean
 
lough
a long narrow (nearly landlocked) cove in Ireland
 
mid-water
the water that is well below the surface but also well above the bottom
 
valence electron
an electron in the outer shell of an atom which can combine with other atoms to form molecules
 
Mount Hubbard
a mountain peak in southeastern Alaska that is part of the Coast Range (14,950 feet high)
 
Canis Major
a constellation to the southeast of Orion; contains Sirius
 
Ping River
a river in western Thailand; a major tributary of the Chao Phraya
 
Antarctic Ocean
the southern waters surrounding Antarctica
 
waterfall
a steep descent of the water of a river
 
Bering Sea
part of the North Pacific between Alaska and Siberia; connected to the Arctic Ocean by the Bering Strait
 
Mackenzie River
a Canadian river; flows into the Beaufort Sea
 
Arctic Ocean
ice covered waters surrounding the North Pole; mostly covered with solid ice or with ice floes and icebergs
 
burrow
a hole made by an animal, usually for shelter
 
Mount Communism
the highest mountain peak in the Pamir Mountains; near the Chinese border in northeastern Tajikistan (24,590 feet high)
 
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