NGB vs bureau

NGB and bureau both are nouns.

Word	Noun	Adjective	Verb	Adverb
NGB	Yes	No	No	No
bureau	Yes	No	No	No

As nouns, bureau is a hypernym of NGB; that is, bureau is a word with a broader meaning than NGB:

NGB: the agency that administers the Army National Guard and the Air National Guard; provides liaison between the Army and the Air Force and various National Guard units
bureau: an administrative unit of government

Other hypernyms of NGB include agency, authority, federal agency, government agency, office.

NGB (noun)	bureau (noun)
the agency that administers the Army National Guard and the Air National Guard; provides liaison between the Army and the Air Force and various National Guard units	furniture with drawers for keeping clothes
	an administrative unit of government