government department vs government

government department and government both are nouns.

Word	Noun	Adjective	Verb	Adverb
government department	Yes	No	No	No
government	Yes	No	No	No

government department (noun)	government (noun)
a department of government	the act of governing; exercising authority
	(government) the system or form by which a community or other political unit is governed
	the study of government of states and other political units
	the organization that is the governing authority of a political unit