The Collaborative International Dictionary of English v.0.48:

Corruption \Cor*rup"tion\ (k?r-r?p"sh?n), n. [F. corruption, L.
   corruptio.]
   1. The act of corrupting or making putrid, or state of being
      corrupt or putrid; decomposition or disorganization, in
      the process of putrefaction; putrefaction; deterioration.
      [1913 Webster]

            The inducing and accelerating of putrefaction is a
            subject of very universal inquiry; for corruption is
            a reciprocal to "generation".         --Bacon.
      [1913 Webster]

   2. The product of corruption; putrid matter.
      [1913 Webster]

   3. The act of corrupting or of impairing integrity, virtue,
      or moral principle; the state of being corrupted or
      debased; loss of purity or integrity; depravity;
      wickedness; impurity; bribery.
      [1913 Webster]

            It was necessary, by exposing the gross corruptions
            of monasteries, . . . to exite popular indignation
            against them.                         --Hallam.
      [1913 Webster]

            They abstained from some of the worst methods of
            corruption usual to their party in its earlier days.
                                                  --Bancroft.
      [1913 Webster]

   Note: Corruption, when applied to officers, trustees, etc.,
         signifies the inducing a violation of duty by means of
         pecuniary considerations. --Abbott.
         [1913 Webster]

   4. The act of changing, or of being changed, for the worse;
      departure from what is pure, simple, or correct; as, a
      corruption of style; corruption in language.
      [1913 Webster]

   Corruption of blood (Law), taint or impurity of blood, in
      consequence of an act of attainder of treason or felony,
      by which a person is disabled from inheriting any estate
      or from transmitting it to others.
      [1913 Webster]

            Corruption of blood can be removed only by act of
            Parliament.                           --Blackstone.

   Syn: Putrescence; putrefaction; defilement; contamination;
        deprivation; debasement; adulteration; depravity; taint.
        See Depravity.
        [1913 Webster]

WordNet (r) 3.0 (2006):

corruption
    n 1: lack of integrity or honesty (especially susceptibility to
         bribery); use of a position of trust for dishonest gain
         [syn: corruptness, corruption] [ant: incorruption,
         incorruptness]
    2: in a state of progressive putrefaction [syn: putrescence,
       putridness, rottenness, corruption]
    3: decay of matter (as by rot or oxidation)
    4: moral perversion; impairment of virtue and moral principles;
       "the luxury and corruption among the upper classes"; "moral
       degeneracy followed intellectual degeneration"; "its
       brothels, its opium parlors, its depravity"; "Rome had fallen
       into moral putrefaction" [syn: corruption, degeneracy,
       depravation, depravity, putrefaction]
    5: destroying someone's (or some group's) honesty or loyalty;
       undermining moral integrity; "corruption of a minor"; "the
       big city's subversion of rural innocence" [syn: corruption,
       subversion]
    6: inducement (as of a public official) by improper means (as
       bribery) to violate duty (as by commiting a felony); "he was
       held on charges of corruption and racketeering"

Moby Thesaurus II by Grady Ward, 1.0:

206 Moby Thesaurus words for "corruption":
   abandon, abandonment, abjection, abomination, abuse of terms,
   acrostic, adulteration, alienation, amphibologism, amphiboly,
   anagram, antiphrasis, atrocity, bad, bane, barbarism, bastardizing,
   befouling, befoulment, biodegradability, biodegradation, blight,
   brainwashing, breakup, bribery, bribery and corruption, bribing,
   cacoepy, cacology, calembour, carrion, college of Laputa,
   colloquialism, contamination, corrosion, corruptedness,
   corruptness, counterindoctrination, criminality, crookedness,
   crying evil, cutting, damage, dandruff, debasement, decadence,
   decadency, decay, decomposition, defilement, degeneracy,
   degenerateness, degeneration, degradability, degradation,
   demoralization, depravation, depravedness, depravity, despoliation,
   destruction, detriment, deviousness, dilapidation, dilution,
   dishonesty, dishonor, disintegration, disorganization,
   dissoluteness, dissolution, doctoring, envenoming, equivocality,
   equivoque, evasiveness, evil, excrement, false coloring,
   feloniousness, festering, filth, fortifying, foul matter, fouling,
   fraudulence, fraudulency, furfur, gammacism, gangrene, graft,
   grievance, harm, havoc, hurt, ill, improbity, impropriety,
   indirection, indoctrination, infection, infelicity, injury,
   jeu de mots, lacing, lambdacism, localism, logogram, logogriph,
   malapropism, mess, metagram, mildew, mischief, misconstruction,
   misdirection, misguidance, misinformation, misinstruction,
   misinterpretation, misknowledge, misleading, mispronunciation,
   misrepresentation, missaying, misspeaking, misteaching, misusage,
   misuse, mold, moral pollution, moral turpitude, muck, mucus,
   mystification, mytacism, obfuscation, obscenity, obscurantism,
   obscuration, ordure, outrage, oxidation, oxidization, palindrome,
   paralambdacism, pararhotacism, paronomasia, perversion,
   play on words, poison, poisoning, pollution, profligacy,
   prostitution, pun, punning, pus, putrid matter, reindoctrination,
   reprobacy, resolution, rhotacism, rot, rottenness, rust, scurf,
   scuz, shadiness, shiftiness, slang, slanting, slime, slipperiness,
   smut, snot, solecism, sophistry, sordes, spiking, spoilage,
   spoonerism, straining, subornation, subversion, suppuration,
   taboo word, the worst, torturing, toxin, trickiness, turpitude,
   unconscientiousness, underhandedness, ungrammaticism, unsavoriness,
   unscrupulousness, unstraightforwardness, venom, vexation,
   vitiation, vulgarism, watering, woe, wordplay, wrong