annul vs repeal

annul is not a noun while repeal is a noun.

Word	Noun	Adjective	Verb	Adverb
annul	No	No	Yes	No
repeal	Yes	No	Yes	No

As verbs, annul and repeal are synonyms defined as:

Other synonyms of annul include countermand, lift, overturn, rescind, reverse, revoke, vacate.

annul (noun)	repeal (noun)
	the act of abrogating; an official or legal cancellation

annul (verb)	repeal (verb)
cancel officially	cancel officially
declare invalid