The Collaborative International Dictionary of English v.0.48:

Tamarind \Tam"a*rind\, n. [It. tamarindo, or Sp. tamarindo, or
   Pg. tamarindo, tamarinho, from Ar. tamarhind[imac],
   literally, Indian date; tamar a dried date + Hind India: cf.
   F. tamarin. Cf. Hindu.] (Bot.)
   1. A leguminous tree (Tamarindus Indica) cultivated both
      the Indies, and the other tropical countries, for the sake
      of its shade, and for its fruit. The trunk of the tree is
      lofty and large, with wide-spreading branches; the flowers
      are in racemes at the ends of the branches. The leaves are
      small and finely pinnated.
      [1913 Webster]

   2. One of the preserved seed pods of the tamarind, which
      contain an acid pulp, and are used medicinally and for
      preparing a pleasant drink.
      [1913 Webster]

   Tamarind fish, a preparation of a variety of East Indian
      fish with the acid pulp of the tamarind fruit.

   Velvet tamarind.
      (a) A West African leguminous tree (Codarium
          acutifolium).
      (b) One of the small black velvety pods, which are used
          for food in Sierra Leone.

   Wild tamarind (Bot.), a name given to certain trees
      somewhat resembling the tamarind, as the Lysiloma
      latisiliqua of Southern Florida, and the Pithecolobium
      filicifolium of the West Indies.
      [1913 Webster]

WordNet (r) 3.0 (2006):

tamarind
    n 1: long-lived tropical evergreen tree with a spreading crown
         and feathery evergreen foliage and fragrant flowers
         yielding hard yellowish wood and long pods with edible
         chocolate-colored acidic pulp [syn: tamarind, tamarind
         tree, tamarindo, Tamarindus indica]
    2: large tropical seed pod with very tangy pulp that is eaten
       fresh or cooked with rice and fish or preserved for curries
       and chutneys [syn: tamarind, tamarindo]