Source : Webster's Revised Unabridged Dictionary (1913)

Bugger \Bug"ger\, n. [F. bougre, fr. LL. Bulgarus, a Bulgarian,
   and also a heretic; because the inhabitants of Bulgaria were
   infected with heresy. Those guilty of the crime of buggery
   were called heretics, because in the eyes of their
   adversaries there was nothing more heinous than heresy, and
   it was therefore thought that the origin of such a vice could
   only be owing to heretics.]
   1. One guilty of buggery or unnatural vice; a sodomite.

   2. A wretch; -- sometimes used humorously or in playful
      disparagement. [Low]

Source : WordNet®

bugger
     v : practice anal sex upon [syn: {sodomize}, {sodomise}]

bugger
     n : someone who engages in anal copulation (especially a male
         who engages in anal copulation with another male) [syn: {sodomite},
          {sodomist}, {sod}]