Parnaiba vs river

Parnaiba and river both are nouns.

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

Parnaiba (noun)	river (noun)
a river in northeastern Brazil that flows generally northward to the Atlantic Ocean	a large natural stream of water (larger than a creek)