USA vs North American nation

USA and North American nation both are nouns.

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

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