The Collaborative International Dictionary of English v.0.48:

Acquit \Ac*quit"\, p. p.
   Acquitted; set free; rid of. [Archaic] --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Acquit \Ac*quit"\, v. t. [imp. & p. p. Acquitted; p. pr. & vb.
   n. Acquitting.] [OE. aquiten, OF. aquiter, F. acquitter; ?
   (L. ad) + OF. quiter, F. quitter, to quit. See Quit, and
   cf. Acquiet.]
   1. To discharge, as a claim or debt; to clear off; to pay
      off; to requite.
      [1913 Webster]

            A responsibility that can never be absolutely
            acquitted.                            --I. Taylor.
      [1913 Webster]

   2. To pay for; to atone for. [Obs.] --Shak.
      [1913 Webster]

   3. To set free, release or discharge from an obligation,
      duty, liability, burden, or from an accusation or charge;
      -- now followed by of before the charge, formerly by from;
      as, the jury acquitted the prisoner; we acquit a man of
      evil intentions.
      [1913 Webster]

   4. Reflexively:
      (a) To clear one's self. --Shak.
      (b) To bear or conduct one's self; to perform one's part;
          as, the soldier acquitted himself well in battle; the
          orator acquitted himself very poorly.
          [1913 Webster]

   Syn: To absolve; clear; exonerate; exonerate; exculpate;
        release; discharge. See Absolve.
        [1913 Webster]

WordNet (r) 3.0 (2006):

acquit
    v 1: pronounce not guilty of criminal charges; "The suspect was
         cleared of the murder charges" [syn: acquit, assoil,
         clear, discharge, exonerate, exculpate] [ant:
         convict]
    2: behave in a certain manner; "She carried herself well"; "he
       bore himself with dignity"; "They conducted themselves well
       during these difficult times" [syn: behave, acquit,
       bear, deport, conduct, comport, carry]

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "acquit":
   absolve, amnesty, bear, carry, clear, comport, conduct, convict,
   decontaminate, demean, deport, destigmatize, discharge, dismiss,
   dispense from, exculpate, excuse, exempt, exempt from, exonerate,
   forgive, free, give absolution, go on, grant amnesty to,
   grant immunity, grant remission, justify, let go, let off,
   liberate, nonpros, pardon, pass sentence, penalize, purge,
   quash the charge, quit, release, remit, set free, shrive,
   vindicate, whitewash, withdraw the charge