Source : Webster's Revised Unabridged Dictionary (1913)

Degeneration \De*gen`er*a"tion\, n. [Cf. F.
   d['e]g['e]n['e]ration.]
   1. The act or state of growing worse, or the state of having
      become worse; decline; degradation; debasement;
      degeneracy; deterioration.

            Our degeneration and apostasy.        --Bates.

   2. (Physiol.) That condition of a tissue or an organ in which
      its vitality has become either diminished or perverted; a
      substitution of a lower for a higher form of structure;
      as, fatty degeneration of the liver.

   3. (Biol.) A gradual deterioration, from natural causes, of
      any class of animals or plants or any particular organ or
      organs; hereditary degradation of type.

   4. The thing degenerated. [R.]

            Cockle, aracus, . . . and other degenerations. --Sir
                                                  T. Browne.

   {Amyloid degeneration}, {Caseous degeneration}, etc. See
      under {Amyloid}, {Caseous}, etc.

Source : WordNet®

degeneration
     n 1: the process of declining from a higher to a lower level of
          effective power or vitality or essential quality [syn: {devolution}]
          [ant: {development}]
     2: the state of being degenerate in mental or moral qualities
        [syn: {degeneracy}, {decadence}, {decadency}]
     3: passing from a more complex to a simpler biological form
        [syn: {retrogression}]