Cancel

Verb

 * 1)  To cross out something with lines etc.
 * 2)  To invalidate or annul something.
 * He cancelled his order on their website.
 * 1)  To mark something (such as a used postage stamp) so that it can't be reused.
 * This machine cancels the letters that have a valid zip code.
 * 1)  To offset or equalize something.
 * The corrective feedback mechanism cancels out the noise.
 * 1)   To remove a common factor from both the numerator and denominator of a fraction, or from both sides of an equation.
 * 2)   To stop production of a programme.

Noun

 * 1) A cancellation (US); (nonstandard in some kinds of English).

Synonyms for Cancel
quash, annul, abolish, remove, erase, rescind, expunge, postmark, repeal, nullify, efface, delete, revoke, obliterate, vacate, void, wipe out, rub off.

Antonyms for Cancel
approve, sustain, uphold, maintain, record, confirm, continue, establish, ratify.

Thesaurus
KO, abandon, abbreviate, abolish, abolishment, abolition, abort, abridge, abrogate, abrogation, absolve, accent, accent mark, accommodate, adjust, annihilate, annul, annulment, balance, bar, belay, black out, blot, blot out, blotting, blotting out, blue-pencil, bowdlerize, bring to naught, bring to nothing, buffer, call off, cancel out, canceling, cancellation, cassation, cease, censor, character, come to nothing, compensate, compensate for, complete, coordinate, counteract, counterbalance, countermand, counterorder, counterpoise, countervail, cross out, custos, cut, cut it out, declare a moratorium, defeasance, dele, delete, deletion, deny, deracinate, desist, direct, disannul, discontinue, dispose of, do away with, dot, drop, drop it, drop the curtain, edit, edit out, efface, effacement, eliminate, end, end off, equalize, equate, eradicate, erase, erasure, even, even up, expression mark, expunction, expunge, expurgate, extinguish, fermata, finalize, finish, fit, fold up, frustrate, get it over, get over with, get through with, give over, give the quietus, give up, halt, have done with, hold, integrate, invalidate, invalidation, kayo, key signature, kibosh, kill, knock it off, knock out, lay off, lead, leave off, level, ligature, make up for, make void, mark, measure, metronomic mark, negate, negativate, negative, neutralize, notation, nullification, nullify, obliterate, obliteration, offset, omit, override, overrule, pause, perfect, poise, polish off, presa, proportion, put paid to, quash, quit, raze, recall, recant, recantation, redeem, refrain, relinquish, renege, renounce, repeal, repudiate, rescind, rescinding, rescindment, rescission, retract, retraction, reversal, reverse, revocation, revoke, revokement, rub out, rule out, scrag, scratch, scratch out, scrub, scrubbing, segno, set aside, setting aside, shoot down, sign, signature, slur, sponge, sponge out, square, stay, stop, strike, strike a balance, strike off, strike out, stultify, surrender, suspend, suspension, swell, symbol, tempo mark, terminate, thwart, tie, time signature, undo, vacate, vacation, vacatur, vinculum, vitiate, void, voidance, voiding, waive, waiver, waiving, washing out, wipe out, wiping out, withdraw, withdrawal, write off, write-off, zap

Etymology
From Latin cancelli:, diminutive of cancer:.