White House vs government building

White House and government building both are nouns.

Word	Noun	Adjective	Verb	Adverb
White House	Yes	No	No	No
government building	Yes	No	No	No

White House (noun)	government building (noun)
the government building that serves as the residence and office of the President of the United States	a building that houses a branch of government
the chief executive department of the United States government