(n.) The act of invalidating, or the state of being invalidated.

abolishment abolition abrogation annulment cancel canceling cancellation cassation counterbalancing countermand counterorder defeasance disconfirmation disproof disproval disproving explosion expose exposure frustration negation neutralization nullification offsetting recall recantation redargution reductio ad absurdum renege repeal rescinding rescindment rescission retraction reversal revocation revoke revokement setting aside suspension thwarting undoing vacation vacatur vitiation voidance voiding waiver waiving withdrawal write-off