U.S. vs Missouri River

U.S. and Missouri River both are nouns.

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

U.S. (noun)	Missouri River (noun)
the executive and legislative and judicial branches of the federal government of the United States	the longest river in the United States; arises in Montana and flows southeastward to become a tributary of the Mississippi at Saint Louis
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