#1 expiration n. [termination, expiry] a coming to an end of a contract period; "the expiry of his driver's license". wn #2 expiration n. [passing, loss, departure, exit, going, release] euphemistic expressions for death; "thousands mourned his passing". wn #3 expiration n. [exhalation, breathing out] the act of expelling air from the lungs. wn