The Collaborative International Dictionary of English v.0.48:

Grackle \Grac"kle\, n. [Cf. L. graculus jackdaw.] (Zool.)
   (a) One of several American blackbirds, of the family
       Icterid[ae]; as, the rusty grackle (Scolecophagus
       Carolinus); the boat-tailed grackle (see Boat-tail); the
       purple grackle (Quiscalus quiscula, or Q.
       versicolor). See Crow blackbird, under Crow.
   (b) An Asiatic bird of the genus Gracula. See Myna.
       [1913 Webster]

WordNet (r) 3.0 (2006):

grackle
    n 1: glossy black Asiatic starling often taught to mimic speech
         [syn: hill myna, Indian grackle, grackle, Gracula
         religiosa]
    2: long-tailed American blackbird having iridescent black
       plumage [syn: grackle, crow blackbird]