[1] : The Collaborative International Dictionary of English v.0.48

pignut \pig"nut\ pi^g"nu^t, n. bot.
   a see groundnut
   d .
   b the bitter-flavored nut of a species of hickory carya
       glabra syn. carya porcina; also, the tree itself.
       1913 webster
see also:
groundnut carya glabra carya porcina 

[2] : The Collaborative International Dictionary of English v.0.48

hickory \hick"ory\, n. north american indian pawcohiccora
   capt. j. smith a kind of milk or oily liquor pressed from
   pounded hickory nuts. "pohickory" is named in a list of
   virginia trees, in 1653, and this was finally shortened to
   "hickory." --j. h. trumbull. bot.
   an american tree of the genus carya, of which there are
   several species. the shagbark is the carya alba, and has a
   very rough bark; it affords the hickory nut of the markets.
   the pignut, or brown hickory, is the carya glabra. the
   swamp hickory is carya amara, having a nut whose shell is
   very thin and the kernel bitter.
   1913 webster

   hickory shad. zool.
   a the mattowacca, or fall herring.
   b the gizzard shad.
       1913 webster
see also:
carya carya alba carya glabra carya amara hickory shad 

[3] : WordNet (r) 2.0

carya glabra
     n : an american hickory tree having bitter nuts syn: pignut,
         pignut hickory, brown hickory, black hickory
see also:
pignut pignut hickory brown hickory black hickory 

Carya >> C Words
Carya, definition of term: Carya
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