Tunguska vs river

Tunguska and river both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tunguska	Yes	No	No	No
river	Yes	No	No	No

Tunguska (noun)	river (noun)
a river in southeastern Siberia that flows northwest from Lake Baikal to become a tributary of the Yenisei River	a large natural stream of water (larger than a creek)
a river that arises to the north of Lake Baikal and flows north and west to the Yenisei River
a river in Siberia that flows northwest to become a tributary of the Yenisei River