Yukon River vs U.S.

Yukon River and U.S. both are nouns.

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

Yukon River (noun)	U.S. (noun)
a North American river that flows westward from the Yukon Territory through central Alaska to the Bering Sea	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