river vs Yenisei River

river and Yenisei River both are nouns.

Word	Noun	Adjective	Verb	Adverb
river	Yes	No	No	No
Yenisei River	Yes	No	No	No

river (noun)	Yenisei River (noun)
a large natural stream of water (larger than a creek)	a Russian river in Siberia; rises in mountains near the Mongolian border and flows generally northward into the Kara Sea