Podkamennaya Tunguska River vs river

Podkamennaya Tunguska River and river both are nouns.

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

Podkamennaya Tunguska River (noun)	river (noun)
a river in Siberia that flows northwest to become a tributary of the Yenisei River	a large natural stream of water (larger than a creek)