North American nation vs USA

North American nation and USA both are nouns.

Word	Noun	Adjective	Verb	Adverb
North American nation	Yes	No	No	No
USA	Yes	No	No	No

North American nation (noun)	USA (noun)
any country on the North American continent	the army of the United States of America; the agency that organizes and trains soldiers for land warfare
	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