D defs.my
Entry 3 senses Webster, 1913

Acorn

/āk'-ôrn/ · A·corn · IPA /ˈeɪ.kɔɹn/
01 n. The fruit of the oak, being an oval nut growing in a woody cup or cupule.
  1. 1.
    The fruit of the oak, being an oval nut growing in a woody cup or cupule.
  2. 2.
    A cone-shaped piece of wood on the point of the spindle above the vane, on the mast-head.(Naut.)
  3. 3.
    See Acorn-shell.(Zool.) See: Acorn-shell