declare vs strike down

declare and strike down both are verbs.

Word	Noun	Adjective	Verb	Adverb
declare	No	No	Yes	No
strike down	No	No	Yes	No

As verbs, strike down is a hyponym of declare; that is, strike down is a word with a more specific, narrower meaning than declare:

declare (verb)	strike down (verb)
state emphatically and authoritatively	cause to fall by or as if by delivering a blow
state firmly	cause to die, especially suddenly
make a declaration (of dutiable goods) to a customs official	declare null and void; make ineffective
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