pistachio

Pistachio is "a deciduous Asian tree having pinnately compound leaves and nutlike fruits" according to our American Heritage Dictionary, and also "the fruit of this tree, having an edible oily green or yellow kernel." The word pistachio comes from the Italian pistacchio, and before that the Latin pistacium, for pistachio nut, and previously the Hellenistic Greek πιστακιον, which our dictionary notes "perh" meant pistachio tree. Before this it might be derived from the Middle Persian pistak but that bit of the entry in AHD has an asterisk with it, so it's probably not okay to state it as a complete fact.

I chose this word because I want to eat some pistachio ice cream right now.