declare vs declaration

declare is not a noun while declaration is a noun.

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

declare (noun)	declaration (noun)
	a statement that is emphatic and explicit (spoken or written)
	a formal expression by a meeting; agreed to by a vote
	(law) unsworn statement that can be admitted in evidence in a legal transaction
	a formal public statement
	(contract bridge) the highest bid becomes the contract setting the number of tricks that the bidder must make
	a statement of taxable goods or of dutiable properties

declare (verb)	declaration (verb)
state emphatically and authoritatively
state firmly
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