one dollar bill vs U.S.

one dollar bill and U.S. both are nouns.

Word	Noun	Adjective	Verb	Adverb
one dollar bill	Yes	No	No	No
U.S.	Yes	No	No	No

one dollar bill (noun)	U.S. (noun)
a piece of paper money worth one dollar	the executive and legislative and judicial branches of the federal government 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