USA vs Arkansas

USA and Arkansas both are nouns.

Word	Noun	Adjective	Verb	Adverb
USA	Yes	No	No	No
Arkansas	Yes	No	No	No

USA (noun)	Arkansas (noun)
the army of the United States of America; the agency that organizes and trains soldiers for land warfare	a state in south central United States; one of the Confederate states during the American Civil War
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 river that rises in the Rocky Mountains in Colorado and flows southeast through Kansas and Oklahoma and through Arkansas to become a tributary of the Mississippi River