The Collaborative International Dictionary of English v.0.48:

Degenerate \De*gen"er*ate\, v. i. [imp. & p. p. Degenerated;
   p. pr. & vb. n. Degenerating.]
   1. To be or grow worse than one's kind, or than one was
      originally; hence, to be inferior; to grow poorer, meaner,
      or more vicious; to decline in good qualities; to
      deteriorate.
      [1913 Webster]

            When wit transgresseth decency, it degenerates into
            insolence and impiety.                --Tillotson.
      [1913 Webster]

   2. (Biol.) To fall off from the normal quality or the healthy
      structure of its kind; to become of a lower type.
      [1913 Webster]