The origin seems to be Persian (from where the plant comes actually as many other fruits) from which the word entered as a loan to ancient Greek (πιστάκιον) and later Latin (pistācium).
Interestingly enough from middle Persian “pstk’” the initial sound became aspirated (like the “Farsi” name itself for the modern language from Middle Persian “Pārsīk”).
And by Turkish/Ottoman domination the f- variant spread in the Middle East.
A lot of fruits, trees and nuts come from Persia… the name of the “peach” in some European languages is closely related to it, for example English “peach” from old French “pesche” is a contraction of medieval latin “persica”, cfr Romanian “piersică”, Italian “pesca” (and in some Italian dialects it’s called “persica”/“persego”) and similar variations.
Relevant detail: Ottoman Turkish ⟨فستق⟩ fıstık borrowed it from Arabic ⟨فُسْتُق⟩ fustuq, that borrowed it from Middle Persian - the same variety as Greek and then Latin did. So odds are that the f-variation was caused by Arabic rendering a foreign [p] as [f], and probably predates Persian itself internally undergoing a p→f shift. Source.
The origin seems to be Persian (from where the plant comes actually as many other fruits) from which the word entered as a loan to ancient Greek (πιστάκιον) and later Latin (pistācium).
Interestingly enough from middle Persian “pstk’” the initial sound became aspirated (like the “Farsi” name itself for the modern language from Middle Persian “Pārsīk”).
And by Turkish/Ottoman domination the f- variant spread in the Middle East.
A lot of fruits, trees and nuts come from Persia… the name of the “peach” in some European languages is closely related to it, for example English “peach” from old French “pesche” is a contraction of medieval latin “persica”, cfr Romanian “piersică”, Italian “pesca” (and in some Italian dialects it’s called “persica”/“persego”) and similar variations.
Relevant detail: Ottoman Turkish ⟨فستق⟩ fıstık borrowed it from Arabic ⟨فُسْتُق⟩ fustuq, that borrowed it from Middle Persian - the same variety as Greek and then Latin did. So odds are that the f-variation was caused by Arabic rendering a foreign [p] as [f], and probably predates Persian itself internally undergoing a p→f shift. Source.