Klamath River vs river

Klamath River and river both are nouns.

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

Klamath River (noun)	river (noun)
a river flowing southwest from Oregon through northern California to the Pacific Ocean	a large natural stream of water (larger than a creek)