U.S. vs NATO

U.S. and NATO both are nouns.

Word	Noun	Adjective	Verb	Adverb
U.S.	Yes	No	No	No
NATO	Yes	No	No	No

U.S. (noun)	NATO (noun)
the executive and legislative and judicial branches of the federal government of the United States	an international organization created in 1949 by the North Atlantic Treaty for purposes of collective security
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