Italian pistacchio, from Latin pistacium pistachio nut, from
Greek pistakion, from pistakē pistachio tree, of Iranian origin;
akin to Persian pistah pistachio tree First Known Use: 1598 Any
of nine species of aromatic trees and shrubs, some ornamental,
that make up the genus Pistacia of the sumac (or cashew) family,
native to Eurasia, with one species in southwestern North
America and another in the Canary Islands. Commercial pistachio
nuts are seeds from the fruit of P. vera. They have a pleasing,
mild, resinous flavour and are used extensively as food and for
yellowish green colouring in confections. The tree bears leaves
with thick, wide, leathery, featherlike leaflets and small fruit
in clusters.