Source : Webster's Revised Unabridged Dictionary (1913)

Bend \Bend\, n. [AS. bend. See {Band}, and cf. the preceding
   noun.]
   1. A band. [Obs.] --Spenser.

   2. [OF. bende, bande, F. bande. See {Band}.] (Her.) One of
      the honorable ordinaries, containing a third or a fifth
      part of the field. It crosses the field diagonally from
      the dexter chief to the sinister base.

   {Bend sinister} (Her.), an honorable ordinary drawn from the
      sinister chief to the dexter base.

Source : WordNet®

bend sinister
     n : a mark of bastardy; lines from top right to bottom left
         [syn: {bar sinister}]