The Collaborative International Dictionary of English v.0.48:

Convict \Con*vict"\ (k[o^]n*v[i^]kt"), p. a. [L. convictus, p.
   p. of convincere to convict, prove. See Convice.]
   Proved or found guilty; convicted. [Obs.] --Shak.
   [1913 Webster]

         Convict by flight, and rebel to all law. --Milton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Convict \Con"vict\ (k[o^]n"v[i^]kt), n.
   1. A person proved guilty of a crime alleged against him; one
      legally convicted or sentenced to punishment for some
      crime.
      [1913 Webster]

   2. A criminal sentenced to penal servitude.

   Syn: Malefactor; culprit; felon; criminal.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Convict \Con*vict"\ (k[o^]n*v[i^]kt"), v. t. [imp. & p. p.
   Convicted; p. pr. & vb. n. Convicting.]
   1. To prove or find guilty of an offense or crime charged; to
      pronounce guilty, as by legal decision, or by one's
      conscience.
      [1913 Webster]

            He [Baxter] . . . had been convicted by a jury.
                                                  --Macaulay.
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            They which heard it, being convicted by their own
            conscience, went out one by one.      --John viii.
                                                  9.
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   2. To prove or show to be false; to confute; to refute.
      [Obs.] --Sir T. Browne.
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   3. To demonstrate by proof or evidence; to prove.
      [1913 Webster]

            Imagining that these proofs will convict a
            testament, to have that in it which other men can
            nowhere by reading find.              --Hooker.
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   4. To defeat; to doom to destruction. [Obs.]
      [1913 Webster]

            A whole armado of convicted sail.     --Shak.

   Syn: To confute; defect; convince; confound.
        [1913 Webster]

WordNet (r) 3.0 (2006):

convict
    n 1: a person serving a sentence in a jail or prison [syn:
         convict, con, inmate, yard bird, yardbird]
    2: a person who has been convicted of a criminal offense
    v 1: find or declare guilty; "The man was convicted of fraud and
         sentenced" [ant: acquit, assoil, clear, discharge,
         exculpate, exonerate]

Moby Thesaurus II by Grady Ward, 1.0:

84 Moby Thesaurus words for "convict":
   Judas, POW, acquit, anathematize, assure, attaint, be convincing,
   betrayer, blacklist, bring home to, bring over, bring round,
   bring to reason, cageling, captive, carry conviction, censure,
   chain gang, con, condemn, convert, convince, criminal, crook, damn,
   deceiver, denounce, denunciate, desperado, desperate criminal,
   detenu, doom, double-dealer, drive home to, ex-convict,
   excommunicate, felon, find guilty, fugitive, gallows bird,
   gangster, gaolbird, inspire belief, internee, jailbird, lag,
   lawbreaker, lead to believe, lifer, loser, mobster, outlaw,
   parolee, pass sentence, pass sentence on, penalize, persuade,
   political prisoner, prisoner, prisoner of war, pronounce judgment,
   pronounce sentence, proscribe, public enemy, quisling, racketeer,
   recidivist, repeater, satisfy, scofflaw, sell, sell one on,
   sentence, stir bird, swindler, talk over, thief, thug,
   ticket-of-leave man, ticket-of-leaver, traitor, trusty, two-timer,
   win over



Bouvier's Law Dictionary, Revised 6th Ed (1856):

CONVICT. One who has been condemned by a competent court. This term is wore
commonly applied to one who has been convicted of a crime or misdemeanor.
There are various local acts which punish the importation of convicts.