The Collaborative International Dictionary of English v.0.48:

Renounce \Re*nounce"\ (r[-e]*nouns"), v. t. [imp. & p. p.
   Renounced (-nounst"); p. pr. & vb. n. Renouncing
   (-noun"s?ng).] [F. renoncer, L. renuntiare to bring back
   word, announce, revoke, retract, renounce; pref. re- re- +
   nuntiare to announce, fr. nuncius, a messenger. See Nuncio,
   and cf. Renunciation.]
   1. To declare against; to reject or decline formally; to
      refuse to own or acknowledge as belonging to one; to
      disclaim; as, to renounce a title to land or to a throne.
      [1913 Webster]

   2. To cast off or reject deliberately; to disown; to dismiss;
      to forswear.
      [1913 Webster]

            This world I do renounce, and in your sights
            Shake patiently my great affliction off. --Shak.
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   3. (Card Playing) To disclaim having a card of (the suit led)
      by playing a card of another suit.
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   To renounce probate (Law), to decline to act as the
      executor of a will. --Mozley & W.
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   Syn: To cast off; disavow; disown; disclaim; deny; abjure;
        recant; abandon; forsake; quit; forego; resign;
        relinquish; give up; abdicate.

   Usage: Renounce, Abjure, Recant. -- To renounce is to
          make an affirmative declaration of abandonment. To
          abjure is to renounce with, or as with, the solemnity
          of an oath. To recant is to renounce or abjure some
          proposition previously affirmed and maintained.
          [1913 Webster]

                From Thebes my birth I own; . . . since no
                disgrace
                Can force me to renounce the honor of my race.
                                                  --Dryden.
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                Either to die the death, or to abjure
                Forever the society of man.       --Shak.
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                Ease would recant
                Vows made in pain, as violent and void.
                                                  --Milton.
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The Collaborative International Dictionary of English v.0.48:

Renounce \Re*nounce"\, v. i.
   1. To make renunciation. [Obs.]
      [1913 Webster]

            He of my sons who fails to make it good,
            By one rebellious act renounces to my blood.
                                                  --Dryden.
      [1913 Webster]

   2. (Law) To decline formally, as an executor or a person
      entitled to letters of administration, to take out probate
      or letters.
      [1913 Webster]

            Dryden died without a will, and his widow having
            renounced, his son Charles administered on June 10.
                                                  --W. D.
                                                  Christie.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Renounce \Re*nounce"\, n. (Card Playing)
   Act of renouncing.
   [1913 Webster]

WordNet (r) 3.0 (2006):

renounce
    v 1: give up, such as power, as of monarchs and emperors, or
         duties and obligations; "The King abdicated when he married
         a divorcee" [syn: abdicate, renounce]
    2: leave (a job, post, or position) voluntarily; "She vacated
       the position when she got pregnant"; "The chairman resigned
       when he was found to have misappropriated funds" [syn:
       vacate, resign, renounce, give up]
    3: turn away from; give up; "I am foreswearing women forever"
       [syn: foreswear, renounce, quit, relinquish]
    4: cast off; "She renounced her husband"; "The parents
       repudiated their son" [syn: disown, renounce,
       repudiate]

Moby Thesaurus II by Grady Ward, 1.0:

157 Moby Thesaurus words for "renounce":
   abandon, abdicate, abjure, abort, abstain from, acknowledge defeat,
   assert the contrary, avoid, back down, back out, backwater,
   beg a truce, belay, belie, brush aside, cancel, capitulate, cease,
   cede, chuck, chuck out, climb down, come off, come to terms,
   contemn, contest, contradict, contravene, controvert, counter,
   crawfish out, cross, cry pax, cry quits, cut it out, cut out,
   decline, demit, deny, desert, desist, desist from, despise,
   disaffirm, disallow, disapprove, disavow, discard, disclaim,
   discontinue, discount, disdain, disgorge, dismiss, disown,
   dispense with, dispose of, disprove, dispute, disregard, disuse,
   do without, drop, drop it, dump, eat crow, eat humble pie, end,
   eschew, except, exclude, forgo, forsake, forswear, gainsay,
   get along without, get rid of, give away, give over, give up, halt,
   hand over, have done with, hold, ignore, implore mercy, impugn,
   join issue upon, kiss good-bye, knock it off, lay down, lay off,
   leave off, let go, make a sacrifice, nol-pros, not accept,
   not admit, not pursue with, nullify, oppose, part with, pass by,
   pass up, pray for quarter, push aside, put behind one, quit,
   quitclaim, rebuff, recant, refrain, refuse, refuse to admit,
   refuse to consider, refute, reject, relinquish, render up, renege,
   repel, repudiate, repulse, resign, retract, revoke, sacrifice,
   say uncle, scout, scrub, shove away, shun, spare, spurn, stay,
   stop, surrender, swallow, swear off, take back, take issue with,
   take the pledge, terminate, throw, throw away, throw off,
   throw out, throw up, turn, turn away, turn out, unsay, vacate,
   waive, withdraw, yield, yield the palm