The Collaborative International Dictionary of English v.0.48:

Truncate \Trun"cate\, v. t. [imp. & p. p. Truncated; p. pr. &
   vb. n. Truncating.] [L. truncatus, p. p. of truncare to cut
   off, mutilate, fr. truncus maimed, mutilated, cut short. See
   Trunk.]
   To cut off; to lop; to maim.
   [1913 Webster]