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

walnut \wal"nut\, n. oe. walnot, as. wealh-hnutu a welsh or
   foreign nut, a walnut; wealh foreign, strange, n., a
   welshman, celt akin to ohg. walh, properly, a celt, from the
   name of a celtic tribe, in l. volcae + hnutu a nut; akin to
   d. walnoot, g. walnuss, icel. valhnot, sw. valn"ot, dan
   valn"od. see nut, and cf. welsh. bot.
   the fruit or nut of any tree of the genus juglans; also,
   the tree, and its timber. the seven or eight known species
   are all natives of the north temperate zone.
   1913 webster
   1913 webster

   note: in some parts of america, especially in new england,
         the name walnut is given to several species of hickory
         carya, and their fruit.
         1913 webster

   ash-leaved walnut, a tree juglans fraxinifolia, native
      in transcaucasia.

   black walnut, a north american tree juglans nigra
      valuable for its purplish brown wood, which is extensively
      used in cabinetwork and for gunstocks. the nuts are
      thick-shelled, and nearly globular.

   english walnut, or european walnut, a tree juglans
      regia, native of asia from the caucasus to japan,
      valuable for its timber and for its excellent nuts, which
      are also called madeira nuts.

   walnut brown, a deep warm brown color, like that of the
      heartwood of the black walnut.

   walnut oil, oil extracted from walnut meats. it is used in
      cooking, making soap, etc.

   white walnut, a north american tree juglans cinerea,
      bearing long, oval, thick-shelled, oily nuts, commonly
      called butternuts. see butternut.
      1913 webster
see also:
nut welsh juglans carya ash-leaved walnut juglans fraxinifolia 
black walnut juglans nigra english walnut european walnut juglans regia 
madeira nuts walnut brown walnut oil white walnut juglans cinerea 
butternuts butternut 

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

butternut \but"ternut`\, n.
   1. bot. an american tree juglans cinerea of the walnut
      family, and its edible fruit; -- so called from the oil
      contained in the latter. sometimes called oil nut and
      white walnut.
      1913 webster

   2. bot. the nut of the caryocar butyrosum and caryocar
      nuciferum, of s. america; -- called also souari nut.
      1913 webster
see also:
juglans cinerea oil nut white walnut caryocar butyrosum caryocar nuciferum souari nut 

[3] : WordNet (r) 2.0

juglans cinerea
     n : north american walnut tree having light-brown wood and
         edible nuts; source of a light-brown dye syn: butternut,
          butternut tree, white walnut
see also:
butternut butternut tree white walnut 

Juglans >> J Words
Juglans, definition of term: Juglans
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