Source : Webster's Revised Unabridged Dictionary (1913)

Revenge \Re*venge"\, v. t. [imp. & p. p. {Revenged}, p. pr. &
   vb. n. {Revenging}.] [OF. revengier, F. revancher; pref. re-
   re- + OF. vengier to avenge, revenge, F. venger, L.
   vindicare. See {Vindicate}, {Vengerance}, and cf.
   {Revindicate}.]
   1. To inflict harm in return for, as an injury, insult, etc.;
      to exact satisfaction for, under a sense of injury; to
      avenge; -- followed either by the wrong received, or by
      the person or thing wronged, as the object, or by the
      reciprocal pronoun as direct object, and a preposition
      before the wrong done or the wrongdoer.

            To revenge the death of our fathers.  --Ld. Berners.

            The gods are just, and will revenge our cause.
                                                  --Dryden.

            Come, Antony, and young Octavius, come, Revenge
            yourselves alone on Cassius.          --Shak.

   2. To inflict injury for, in a spiteful, wrong, or malignant
      spirit; to wreak vengeance for maliciously.

   Syn: To avenge; vindicate. See {Avenge}.

Revenge \Re*venge"\, v. i.
   To take vengeance; -- with upon. [Obs.] ``A bird that will
   revenge upon you all.'' --Shak.

Revenge \Re*venge"\, n.
   1. The act of revenging; vengeance; retaliation; a returning
      of evil for evil.

            Certainly, in taking revenge, a man is even with his
            enemy; but in passing it over he is superior.
                                                  --Bacon.

   2. The disposition to revenge; a malignant wishing of evil to
      one who has done us an injury.

            Revenge now goes To lay a complot to betray thy
            foes.                                 --Shak.

            The indulgence of revenge tends to make men more
            savage and cruel.                     --Kames.

Source : WordNet®

revenge
     n : action taken in return for an injury or offense [syn: {retaliation}]
     v : take revenge for a perceived wrong; "He wants to avenge the
         murder of his brother" [syn: {avenge}, {retaliate}]