Synonyms for Expiration (same or very similar meaning)
WordNet sense 1 (a coming to an end of a contract period):
termination, expiry
WordNet sense 2 (euphemistic expressions for death):
departure, exit, going, loss, passing, release, release
WordNet sense 3 (the act of expelling air from the lungs):
exhalation, breathing out
From the ODE community, based on WordNet
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