The Collaborative International Dictionary of English v.0.48:

Pineapple \Pine"ap`ple\, n. (Bot.)
   A tropical plant (Ananassa sativa); also, its fruit; -- so
   called from the resemblance of the latter, in shape and
   external appearance, to the cone of the pine tree. Its origin
   is unknown, though conjectured to be American.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ananas \A*na"nas\, n. [Sp. ananas, from the native American
   name.] (Bot.)
   The pineapple (Ananassa sativa).
   [1913 Webster]