bureau vs administrative unit

bureau and administrative unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
bureau	Yes	No	No	No
administrative unit	Yes	No	No	No

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

Other hypernyms of bureau include administrative body.

bureau (noun)	administrative unit (noun)
furniture with drawers for keeping clothes	a unit with administrative responsibilities
an administrative unit of government