river vs Weser River

river and Weser River both are nouns.

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

river (noun)	Weser River (noun)
a large natural stream of water (larger than a creek)	a river in northwestern Germany that flows northward to the North Sea near Bremerhaven