river vs Angara River

river and Angara River both are nouns.

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

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