The Collaborative International Dictionary of English v.0.48:

Repudiation \Re*pu`di*a"tion\ (r[-e]*p[=u]`d[i^]*[=a]"sh[u^]n),
   n. [Cf.F. r['e]pudiation, L. repudiatio.]
   The act of repudiating, or the state of being repuddiated;
   as, the repudiation of a doctrine, a wife, a debt, etc.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Repudiation \Re*pu`di*a"tion\, n.
   One who favors repudiation, especially of a public debt.
   [1913 Webster]

WordNet (r) 3.0 (2006):

repudiation
    n 1: rejecting or disowning or disclaiming as invalid;
         "Congressional repudiation of the treaty that the President
         had negotiated" [syn: repudiation, renunciation]
    2: refusal to acknowledge or pay a debt or honor a contract
       (especially by public authorities); "the repudiation of the
       debt by the city"
    3: the exposure of falseness or pretensions; "the debunking of
       religion has been too successful" [syn: repudiation,
       debunking]

Moby Thesaurus II by Grady Ward, 1.0:

148 Moby Thesaurus words for "repudiation":
   abjuration, abjurement, abnegation, abrogation,
   absolute contradiction, agreement to disagree, alienation,
   annulment, apostasy, bad debt, ban, bar, barring, blockade,
   boycott, chucking, chucking out, circumscription, contempt,
   contradiction, contrary assertion, contravention, controversion,
   counter-culture, countering, crossing, debarment, debarring,
   declension, declination, declinature, declining, default,
   defection, delinquence, delinquency, demarcation, denial,
   deprivation, despisal, despising, difference, disaccord,
   disaffirmation, disagreement, disallowance, disapprobation,
   disapproval, disavowal, discard, disclaimer, disclamation,
   discounting, dishonor, dishonoring, dismissal, disobedience,
   disowning, disownment, disparity, disproof, disregard,
   dissatisfaction, dissension, dissent, dissentience, dissidence,
   diversity, dropping out, embargo, exception, exclusion,
   expatriation, forswearing, gainsaying, holding back, ignoring,
   impugnment, inadmissibility, injunction, lockout, minority opinion,
   narrowing, nay, negation, negative, negative answer, nix, no,
   nonacceptance, nonadmission, nonagreement, nonapproval, nonassent,
   noncompliance, nonconcurrence, nonconformity, nonconsent,
   nonconsideration, nondischarge of debts, nonobservance, nonpayment,
   nonremittal, nullification, omission, opposition, palinode,
   palinody, passing by, preclusion, prohibition, protest,
   protested bill, putting away, putting out, rebuff, recantation,
   recusance, recusancy, refusal, refutation, rejection, relegation,
   reneging, renouncement, renunciation, repulse, restriction,
   retention, retractation, retraction, revocation, revokement,
   scouting, secession, spurning, taboo, throwing out, thumbs-down,
   turndown, turning out, uncollectible, underground, unsaying,
   unwillingness, variance, withdrawal, withholding