river vs Orinoco

river and Orinoco both are nouns.

Word	Noun	Adjective	Verb	Adverb
river	Yes	No	No	No
Orinoco	Yes	No	No	No

river (noun)	Orinoco (noun)
a large natural stream of water (larger than a creek)	a South American river 1,500 miles long; flows into the South Atlantic