The Collaborative International Dictionary of English v.0.48:

ackee \ackee\ n.
   1. 1 red pear-shaped tropical fruit with poisonous seeds; its
      flesh is poisonous when unripe or overripe.

   Syn: akee
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

ackee
    n 1: red pear-shaped tropical fruit with poisonous seeds; flesh
         is poisonous when unripe or overripe [syn: ackee, akee]