The Collaborative International Dictionary of English v.0.48:

Sleigh \Sleigh\, n. [Cf. D. & LG. slede, slee, Icel. sle?i. See
   Sled.]
   A vehicle moved on runners, and used for transporting persons
   or goods on snow or ice; -- in England commonly called a
   sledge.
   [1913 Webster]

   Sleigh bell, a small bell attached either to a horse when
      drawing a slegh, or to the sleigh itself; especially a
      globular bell with a loose ball which plays inside instead
      of a clapper.
      [1913 Webster]

WordNet (r) 3.0 (2006):

sleigh bell
    n 1: a bell attached to a sleigh, or to the harness of a horse
         that is pulling a sleigh [syn: sleigh bell, cascabel]

Moby Thesaurus II by Grady Ward, 1.0:

20 Moby Thesaurus words for "sleigh bell":
   bell, chimes, church bell, clapper, cowbell, dinner bell,
   dinner gong, doorbell, fire bell, gong, gong bell, hand bell,
   jingle bell, passing bell, sacring bell, sheepbell, telephone bell,
   tintinnabulum, tongue, triangle