Orinoco vs river

Orinoco and river both are nouns.

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

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