Note: In some parts of America, especially in New England,
         the name walnut is given to several species of hickory
         (Carya), and their fruit.

   Ash-leaved walnut, a tree (Juglans fraxinifolia), native
      in Transcaucasia.

   Black walnut, a North American tree (J. 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, or European, walnut, a tree (J. 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 (J. cinerea), bearing
      long, oval, thick-shelled, oily nuts, commonly called
      butternuts. See Butternut.