U.S. vs American state

U.S. and American state both are nouns.

Word	Noun	Adjective	Verb	Adverb
U.S.	Yes	No	No	No
American state	Yes	No	No	No

U.S. (noun)	American state (noun)
the executive and legislative and judicial branches of the federal government of the United States	one of the 50 states of the United States
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