declare vs authorise

declare and authorise both are verbs.

Word	Noun	Adjective	Verb	Adverb
declare	No	No	Yes	No
authorise	No	No	Yes	No

As verbs, authorise is a hypernym of declare; that is, authorise is a word with a broader meaning than declare:

Other hypernyms of declare include authorize, clear, pass.

declare (verb)	authorise (verb)
state emphatically and authoritatively	grant authorization or clearance for
state firmly	give or delegate power or authority to
make a declaration (of dutiable goods) to a customs official
declare to be
announce publicly or officially
proclaim one's support, sympathy, or opinion for or against
designate (a trump suit or no-trump) with the final bid of a hand
authorize payments of