expire (v.) Look up expire at Dictionary.com
c.1400, "to die," from Middle French expirer (12c.) "expire, elapse," from Latin expirare/exspirare "breathe out, breathe one's last, die," from ex- "out" (see ex-) + spirare "to breathe" (see spirit (n.)). "Die" is the older sense in English; that of "breathe out" is first attested 1580s. Of laws, patents, treaties, etc., mid-15c. Related: Expired; expiring.