Source : Webster's Revised Unabridged Dictionary (1913)

Butment \But"ment\, n. [Abbreviation of {Abutment}.]
   1. (Arch.) A buttress of an arch; the supporter, or that part
      which joins it to the upright pier.

   2. (Masonry) The mass of stone or solid work at the end of a
      bridge, by which the extreme arches are sustained, or by
      which the end of a bridge without arches is supported.

   {Butment cheek} (Carp.), the part of a mortised timber
      surrounding the mortise, and against which the shoulders
      of the tenon bear. --Knight.