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. valnöt, Dan valnöd. 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 ]

☞ 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 ]