Ohio River vs U.S.

Ohio River and U.S. both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ohio River	Yes	No	No	No
U.S.	Yes	No	No	No

Ohio River (noun)	U.S. (noun)
a river that is formed in western Pennsylvania and flows westward to become a tributary of the Mississippi River	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