Same meaning: cancellation, retraction, rescission, annulment

1 cancellation
2 retraction
3 rescission
4 annulment

What is the difference?

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Did you try a DICTIONARY? They are all used in different contexts:

Rescission: (law) the act of rescinding; the cancellation of a contract and the return of the parties to the positions they would have had if the contract had not been made; recission may be brought about by decree or by mutual consent.

Annulment:The invalidation of a marriage, as for nonconsummation, effected by means of a declaration stating that the marriage was never valid; (law) a formal termination (of a relationship or a judicial proceeding etc).

Retraction: withdrawal of a promise, statement, opinion, etc.; a disavowal or taking back of a previous assertion.

Cancellation (a more general word): to destroy the force, effectiveness, or validity of; a calling off usually without expectation of conducting or performing at a later time – as as a reservation for a hotel room, airplane ticket, a cheque, an appointment, a football game, etc.
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