Nouns denoting natural objects (not man-made)

Indus
a faint constellation in the southern hemisphere near Telescopium and Tucana
 
Lehigh River
a river in eastern Pennsylvania that flows southeast into the Delaware River
 
collector
a crater that has collected cosmic material hitting the earth
 
North Channel
a strait between Northern Ireland and Scotland that connects the Atlantic Ocean and the Irish Sea
 
Musca
a small constellation in the polar region of the southern hemisphere near the Southern Cross and Chamaeleon
 
crevice
a long narrow opening
 
Io
the closest of Jupiter's moons; has active volcanoes
 
remains
any object that is left unused or still extant
 
envelope
a natural covering (as by a fluid)
 
Tevere
a river of central Italy; flows through Rome to the Tyrrhenian Sea
 
ice mass
a large mass of ice
 
sialolith
a stone formed in the salivary gland
 
Canadian River
a river rising in northeastern New Mexico and flowing eastward across the Texas panhandle to become a tributary of the Arkansas River in Oklahoma
 
Delaware River
a river that rises in the Catskills in southeastern New York and flows southward along the border of Pennsylvania with New York and New Jersey to northern Delaware where it empties into Delaware Bay
 
piedmont
a gentle slope leading from the base of a mountain to a region of flat land
 
snowdrift
a mass of snow heaped up by the wind
 
Victoria Falls
a large waterfall on the border between Argentina and Brazil
 
Circinus
a small faint constellation in the southern hemisphere near Musca and Triangulum Australe
 
coal
a hot fragment of wood or coal that is left from a fire and is glowing or smoldering
 
loch
a long narrow inlet of the sea in Scotland (especially when it is nearly landlocked)
 
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