river vs Namoi River

river and Namoi River both are nouns.

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

river (noun)	Namoi River (noun)
a large natural stream of water (larger than a creek)	a river in southeastern Australia that flows generally northwest to join the Darling River