USA vs Mid-Atlantic states

USA and Mid-Atlantic states both are nouns.

Word	Noun	Adjective	Verb	Adverb
USA	Yes	No	No	No
Mid-Atlantic states	Yes	No	No	No

USA (noun)	Mid-Atlantic states (noun)
the army of the United States of America; the agency that organizes and trains soldiers for land warfare	a region of the eastern United States comprising New York and New Jersey and Pennsylvania and Delaware and Maryland
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