noun

• The act, process, or result of cancelling; as, the cancellation of certain words in a contract, or of the contract itself.
• (mathematics) The operation of striking out common factors, e.g. in both the dividend and divisor.
• (philately) A postmark that marks a postage stamp so as to prevent its reuse.
• (law) In United States intellectual property law, a proceeding in which an interested party seeks to cancel the registration of a trademark or patent.
• (anatomy) The property of being cancellate.