The Collaborative International Dictionary of English v.0.48:

Chapelet \Chap"e*let\, n. [F. See Chaplet.]
   1. A pair of straps, with stirrups, joined at the top and
      fastened to the pommel or the frame of the saddle, after
      they have been adjusted to the convenience of the rider.
      [Written also chaplet.]
      [1913 Webster]

   2. A kind of chain pump, or dredging machine.
      [1913 Webster]