Source : Webster's Revised Unabridged Dictionary (1913)

Bourdon \Bour"don\, n. [F., fr. L. burdo mule, esp. one used for
   carrying litters. Cf. Sp. muleta a young she mule; also,
   crutch, prop.]
   A pilgrim's staff.

Bourdon \Bour"don`\, n. [F. See {Burden} a refrain.] (Mus.)
   (a) A drone bass, as in a bagpipe, or a hurdy-gurdy. See
       {Burden} (of a song.)
   (b) A kind of organ stop.

Source : WordNet®

bourdon
     n : a pipe of the bagpipe that is tuned to produce a single
         continuous tone [syn: {drone}, {drone pipe}]