local authority vs bureau

local authority and bureau both are nouns.

Word	Noun	Adjective	Verb	Adverb
local authority	Yes	No	No	No
bureau	Yes	No	No	No

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

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

local authority (noun)	bureau (noun)
an administrative unit of local government	furniture with drawers for keeping clothes
	an administrative unit of government