[医] 山核桃属

[ noun ]
genus of large deciduous nut-bearing trees; United States and China
<noun.plant>

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["o]t, Dan
valn["o]d. 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.

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 ({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}.