the edible, juicy, collective fruit of a tropical, bromeliaceous plant, Ananas comosus, that develops from a spike or head of flowers and is surmounted by a crown of leaves.
2.
the plant itself, having a short stem and rigid, spiny-margined, recurved leaves.
3.
Military Slang.a fragmentation hand grenade.
Origin: 1350–1400 for earlier sense; 1655–65for def 1;Middle Englishpinappel pine cone; see pine1, apple
late 14c., "pine cone," from pine (n.) + apple. The reference to the fruit of the tropical plant (from resemblance of shape) is first recorded 1660s, and pine cone emerged 1690s to replace pineapple in its original sense. For "pine cone," O.E. also used pinhnyte "pine nut."