The Collaborative International Dictionary of English v.0.48:

Vengeance \Venge"ance\, n. [F. vengeance, fr. venger to avenge,
   L. vindicare to lay claim to, defend, avenge, fr. vindex a
   claimant, defender, avenger, the first part of which is of
   uncertain origin, and the last part akin to dicere to say.
   See Diction, and cf. Avenge, Revenge, Vindicate.]
   1. Punishment inflicted in return for an injury or an
      offense; retribution; -- often, in a bad sense, passionate
      or unrestrained revenge.
      [1913 Webster]

            To me belongeth vengeance and recompense. --Deut.
                                                  xxxii. 35.
      [1913 Webster]

            To execute fierce vengeance on his foes. --Milton.
      [1913 Webster]

   2. Harm; mischief. [Obs.] --Shak.
      [1913 Webster]

   What a vengeance, or What the vengeance, what! --
      emphatically. [Obs.] "But what a vengeance makes thee
      fly!" --Hudibras. "What the vengeance! Could he not speak
      'em fair?" --Shak.

   With a vengeance,
      (a) with great violence; as, to strike with a vengeance.
          [Colloq.]
      (b) with even greater intensity; as, to return one's
          insult with a vengeance.
          [1913 Webster + PJC]

WordNet (r) 3.0 (2006):

vengeance
    n 1: the act of taking revenge (harming someone in retaliation
         for something harmful that they have done) especially in
         the next life; "Vengeance is mine; I will repay, saith the
         Lord"--Romans 12:19; "For vengeance I would do nothing.
         This nation is too great to look for mere revenge"--James
         Garfield; "he swore vengeance on the man who betrayed him";
         "the swiftness of divine retribution" [syn: vengeance,
         retribution, payback]

Moby Thesaurus II by Grady Ward, 1.0:

30 Moby Thesaurus words for "vengeance":
   avengement, avenging, blood feud, counterblow, energetically,
   enthusiastically, ferociously, feud, fiercely, forcefully,
   furiously, getting even, repayment, reprisal, requital,
   retaliation, retribution, return, revanche, revanchism, revenge,
   revengefulness, sweet revenge, vehemently, vendetta, vengefulness,
   violently, wholeheartedly, wildly, with a vengeance