The Collaborative International Dictionary of English v.0.48:

Insult \In"sult\, n. [L. insultus, fr. insilire to leap upon:
   cf. F. insulte. See Insult, v. t.]
   [1913 Webster]
   1. The act of leaping on; onset; attack. [Obs.] --Dryden.
      [1913 Webster]

   2. Gross abuse offered to another, either by word or act; an
      act or speech of insolence or contempt; a deprecatory
      remark; an affront; an indignity.
      [1913 Webster]

            The ruthless sneer that insult adds to grief.
                                                  --Savage.

   3. (Med., Biology) An injury to an organism; trauma; as, to
      produce an experimental insult to investigate healing
      processes.
      [PJC]

   Syn: Affront; indignity; abuse; outrage; contumely. See
        Affront.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Insult \In*sult"\, v. t. [imp. & p. p. Insulted; p. pr. & vb.
   n. Insulting.] [F. insulter, L. insultare, freq. fr.
   insilire to leap into or upon; pref. in- in, on + salire to
   leap. See Salient.]
   [1913 Webster]
   1. To leap or trample upon; to make a sudden onset upon.
      [Obs.] --Shak.
      [1913 Webster]

   2. To treat with abuse, insolence, indignity, or contempt, by
      word or action; to abuse; as, to call a man a coward or a
      liar, or to sneer at him, is to insult him.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Insult \In*sult"\, v. i.
   1. To leap or jump.
      [1913 Webster]

            Give me thy knife, I will insult on him. --Shak.
      [1913 Webster]

            Like the frogs in the apologue, insulting upon their
            wooden king.                          --Jer. Taylor.
      [1913 Webster]

   2. To behave with insolence; to exult. [Archaic]
      [1913 Webster]

            The lion being dead, even hares insult. --Daniel.
      [1913 Webster]

            An unwillingness to insult over their helpless
            fatuity.                              --Landor.
      [1913 Webster]

WordNet (r) 3.0 (2006):

insult
    n 1: a rude expression intended to offend or hurt; "when a
         student made a stupid mistake he spared them no abuse";
         "they yelled insults at the visiting team" [syn: abuse,
         insult, revilement, contumely, vilification]
    2: a deliberately offensive act or something producing the
       effect of deliberate disrespect; "turning his back on me was
       a deliberate insult" [syn: insult, affront]
    v 1: treat, mention, or speak to rudely; "He insulted her with
         his rude remarks"; "the student who had betrayed his
         classmate was dissed by everyone" [syn: diss, insult,
         affront]

Moby Thesaurus II by Grady Ward, 1.0:

113 Moby Thesaurus words for "insult":
   abase, abuse, affront, airs, arrogance, asperse, aspersion,
   atrocity, barb, be above, be contemptuous of, brickbat, call names,
   care nothing for, clannishness, cliquishness, contemn, contempt,
   contemptuousness, contumely, cut, debase, defamation, defame,
   degrade, deride, despise, despite, dig, discourtesy, disdain,
   disdainfulness, disgrace, dishonor, disoblige, disparage,
   disparagement, disprize, dump, dump on, enormity, exclusiveness,
   feel contempt for, feel superior to, fleer, fleer at, flout,
   flouting, gibe, gibe at, gird, give offense to, hauteur,
   hold beneath one, hold cheap, hold in contempt, humble, humiliate,
   humiliation, hurl a brickbat, ignominy, indignity, injure, injury,
   insolence, invective, jeer, jeer at, jeering, jibe at, libel,
   look down upon, misprize, mock, mockery, obloquy, offend, offense,
   opprobrium, outrage, put down, put-down, rank low, ridicule, rump,
   scoff, scoff at, scorn, scornfulness, scurrility, set at naught,
   shame, slander, slap, slight, slur, sneer, sneer at, sneeze at,
   sniff at, sniffiness, snobbishness, snootiness, snort at,
   snottiness, sovereign contempt, superciliousness, taunt,
   think nothing of, toploftiness, treat with indignity,
   uncomplimentary remark, vituperation