The Collaborative International Dictionary of English v.0.48:

Cocoa \Co"coa\ (k[=o]"k[-o]), n., Cocoa palm \Co"coa palm`\
   (k[=o]"k[-o] p[aum]m`)[Sp. & Pg. coco cocoanut, in Sp. also,
   cocoa palm. The Portuguese name is said to have been given
   from the monkeylike face at the base of the nut, fr. Pg. coco
   a bugbear, an ugly mask to frighten children. Cf., however,
   Gr. koy^ki the cocoa palm and its fruit, ko`i:x, ko`i:kos, a
   kind of Egyptian palm.] (Bot.)
   A tall palm tree producing the cocoanut (Cocos nucifera) as
   its fruit. It grows in nearly all tropical countries,
   attaining a height of sixty or eighty feet. The trunk is
   without branches, and has a tuft of leaves at the top, each
   being fifteen or twenty feet in length, and at the base of
   these the nuts hang in clusters; the cocoanut tree. It is
   widely planted throughout the tropics, and in some locations
   as an ornamental tree.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Cocos nucifera
    n 1: tall palm tree bearing coconuts as fruits; widely planted
         throughout the tropics [syn: coconut, coconut palm,
         coco palm, coco, cocoa palm, coconut tree, Cocos
         nucifera]