The Collaborative International Dictionary of English v.0.48:

Tambourine \Tam`bour*ine"\, n. [F. tambourin; cf. It. tamburino.
   See Tambour, and cf. Tamborine.]
   A small drum, especially a shallow drum with only one skin,
   played on with the hand, and having bells at the sides; a
   timbrel.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tambourine \Tam`bour*ine"\, n.
   A South American wild dove (Tympanistria tympanistria),
   mostly white, with black-tiped wings and tail. Its resonant
   note is said to be ventriloquous.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

tambourine
    n 1: a shallow drum with a single drumhead and with metallic
         disks in the sides

Moby Thesaurus II by Grady Ward, 1.0:

27 Moby Thesaurus words for "tambourine":
   bongo drum, conga, drum, drumhead, drumskin, drumstick, jazz stick,
   kettle, kettledrum, membranophone, side drum, snare, snare drum,
   tabor, taboret, tabret, tam-tam, tenor drum, timbrel, timpani,
   tom-tom, troll-drum, tymp stick, tympan, tympanon, tympanum,
   war drum