The Collaborative International Dictionary of English v.0.48:

Degradation \Deg`ra*da"tion\, n. [LL. degradatio, from
   degradare: cf. F. d['e]gradation. See Degrade.]
   1. The act of reducing in rank, character, or reputation, or
      of abasing; a lowering from one's standing or rank in
      office or society; diminution; as, the degradation of a
      peer, a knight, a general, or a bishop.
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            He saw many removes and degradations in all the
            other offices of which he had been possessed.
                                                  --Clarendon.
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   2. The state of being reduced in rank, character, or
      reputation; baseness; moral, physical, or intellectual
      degeneracy; disgrace; abasement; debasement.
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            The . . . degradation of a needy man of letters.
                                                  --Macaulay.
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            Deplorable is the degradation of our nature.
                                                  --South.
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            Moments there frequently must be, when a sinner is
            sensible of the degradation of his state. --Blair.
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   3. Diminution or reduction of strength, efficacy, or value;
      degeneration; deterioration.
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            The development and degradation of the alphabetic
            forms can be traced.                  --I. Taylor
                                                  (The
                                                  Alphabet).
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   4. (Geol.) A gradual wearing down or wasting, as of rocks and
      banks, by the action of water, frost etc.
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   5. (Biol.) The state or condition of a species or group which
      exhibits degraded forms; degeneration.
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            The degradation of the species man is observed in
            some of its varieties.                --Dana.
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   6. (Physiol.) Arrest of development, or degeneration of any
      organ, or of the body as a whole.
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   Degradation of energy, or Dissipation of energy
      (Physics), the transformation of energy into some form in
      which it is less available for doing work.

   Syn: Abasement; debasement; reduction; decline.
        [1913 Webster]

WordNet (r) 3.0 (2006):

degradation
    n 1: changing to a lower state (a less respected state) [syn:
         degradation, debasement]
    2: a low or downcast state; "each confession brought her into an
       attitude of abasement"- H.L.Menchken [syn: abasement,
       degradation, abjection]

The Devil's Dictionary (1881-1906):

DEGRADATION, n.  One of the stages of moral and social progress from
private station to political preferment.