The Collaborative International Dictionary of English v.0.48:

Expire \Ex*pire"\, v. t. [imp. & p. p. Expired; p. pr & vb. n.
   Expiring.] [L. expirare, exspirare, expiratum, exspiratum;
   ex out + spirare to breathe: cf. F. expirer. See Spirit.]
   1. To breathe out; to emit from the lungs; to throw out from
      the mouth or nostrils in the process of respiration; --
      opposed to inspire.
      [1913 Webster]

            Anatomy exhibits the lungs in a continual motion of
            inspiring and expiring air.           --Harvey.
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            This chafed the boar; his nostrils flames expire.
                                                  --Dryden.
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   2. To give forth insensibly or gently, as a fluid or vapor;
      to emit in minute particles; to exhale; as, the earth
      expires a damp vapor; plants expire odors.
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            The expiring of cold out of the inward parts of the
            earth in winter.                      --Bacon.
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   3. To emit; to give out. [Obs.] --Dryden.
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   4. To bring to a close; to terminate. [Obs.]
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            Expire the term
            Of a despised life.                   --Shak.
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The Collaborative International Dictionary of English v.0.48:

expired \expired\ adj.
   having come to an end or become void after passage of a
   period of time; as, an expired passport; caught driving with
   an expired license. Opposite of unexpired.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

expired
    adj 1: having come to an end or become void after passage of a
           period of time; "an expired passport"; "caught driving
           with an expired license" [ant: unexpired]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "expired":
   ago, all gone, annihilated, antiquated, antique, blown over, by,
   bygone, bypast, dated, dead, dead and buried, deceased, defunct,
   departed, done for, down the drain, elapsed, extinct, finished,
   forgotten, gone, gone glimmering, gone-by, had it, has-been,
   irrecoverable, kaput, kaputt, lapsed, no more, obsolete, over,
   passe, passed, passed away, past, perished, run out, vanished,
   wound up