Source : Webster's Revised Unabridged Dictionary (1913)

Mocker \Mock"er\, n.
   1. One who, or that which, mocks; a scorner; a scoffer; a
      derider.

   2. A deceiver; an impostor.

   3. (Zo["o]l.) A mocking bird.

   {Mocker nut} (Bot.), a kind of hickory ({Carya tomentosa})
      and its fruit, which is far inferior to the true shagbark
      hickory nut.

Source : WordNet®

Carya tomentosa
     n : smooth-barked North American hickory with 7 to 9 leaflets
         bearing a hard-shelled edible nut [syn: {mockernut}, {mockernut
         hickory}, {black hickory}, {white-heart hickory}, {big-bud
         hickory}]