U.S.A. vs Rio Grande

U.S.A. and Rio Grande both are nouns.

Word	Noun	Adjective	Verb	Adverb
U.S.A.	Yes	No	No	No
Rio Grande	Yes	No	No	No

U.S.A. (noun)	Rio Grande (noun)
North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776	a North American river; boundary between the United States and Mexico; flows into Gulf of Mexico