Acorn

Noun

 * 1) The fruit of the oak, being an oval nut growing in a woody cup or cupule.
 * 2)  A cone-shaped piece of wood on the point of the spindle above the vane, on the mast-head.
 * 3)  See acorn-shell.

Derived terms

 * acorn cup
 * acorn nut
 * acorn squash
 * ride a horse foaled by an acorn

Holonyms

 * (fruit of an oak): oak