pis·ta·chi·o (pĭ-stăshē-ō′, -stäshē-ō′)
n. pl. pis·ta·chi·os
1. A deciduous tree (Pistacia vera) of central and western Asia, having pinnately compound leaves and dry, drupaceous, nutlike fruits.
2. The nutlike fruit of this tree, having an edible, oily, green or yellow kernel.
[Ultimately (partly via Middle French pistache) from Italian pistacchio, from Latin pistacium, pistachio nut, from Greek pistakion, from pistakē, pistachio tree, of Iranian origin; akin to Middle Persian pistag.]
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