river vs Sambre River

river and Sambre River both are nouns.

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

river (noun)	Sambre River (noun)
a large natural stream of water (larger than a creek)	a river in western Europe that rises in northern France and flows generally east into Belgium where it joins the Meuse at Namur