pignut

from WordNet (r) 3.0 (2006)

pignut
    n 1: an American hickory tree having bitter nuts [syn: {pignut},
         {pignut hickory}, {brown hickory}, {black hickory}, {Carya
         glabra}]

from The Collaborative International Dictionary of English v.0.48

Groundnut \Ground"nut`\ (ground"n[u^]t`), n. (Bot.)
   (a) The fruit of the {Arachis hypog[ae]a} (native country
       uncertain); the peanut; the earthnut.
   (b) A leguminous, twining plant ({Apios tuberosa}), producing
       clusters of dark purple flowers and having a root
       tuberous and pleasant to the taste.
   (c) The dwarf ginseng ({Aralia trifolia}). [U. S.] --Gray.
   (d) A European plant of the genus {Bunium} ({B. flexuosum}),
       having an edible root of a globular shape and sweet,
       aromatic taste; -- called also {earthnut}, {earth
       chestnut}, {hawknut}, and {pignut}.
       [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Pignut \Pig"nut\ (p[i^]g"n[u^]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]