The story
- Proto-Indo-European*peys-
- Proto-Indo-European*pis-tó-s
- Proto-Indo-Iranian*pištás
- Ancient Greekπιστάκη (pistákē)
- Ancient Greekπιστάκῐον (pistákĭon)
- Latinpistacium
- Italianpistacchio
- English todaypistachio
From Italian pistacchio (1590s), from Latin pistācium (“pistachio”), from Ancient Greek πιστάκιον (pistákion), from πιστάκη (pistákē, “pistachio tree”), of Iranian origin. Compare Middle English pistace (from Middle French pistace, pistache), Northern Kurdish pisteq, Persian پسته (peste), Middle Persian pstk' (pistag, “pistachio nut”), Old Armenian պիստակ (pistak) (from Iranian), Arabic فُسْتُق (fustuq), Turkish fıstık.
Etymology from Wiktionary, CC BY-SA 4.0.