It’s tempting to say that this word is a tough nut to crack. But that wouldn’t be accurate. Better to say it’s the seed of an interesting exploration once you start to pry it open.
Prying open is, certainly for me, the essence of pistachios. The shells are always partly open, sort of like vegan clams, and the one thing a bowl of pistachios will guarantee is that my thumbnails will be separated a bit more from the quick by the bottom of it. And I will get to the bottom of it. Set out a bowl surreptitiously and you will be sure to catch me red-handed.
But not literally, I hope. Please don’t give me the ones that are coated in red colouring or your place will look like a crime scene (and so will my face; you will eventually figure out that I just touch my eyes a lot and am not actually in an emotional crisis). The red colouring isn’t really needed anymore anyway – it was added to hide stains on the shells, but since they’re picked by machine rather than by hand now, it’s not really an issue.
Pistachios are one of those things that are one thing to normal people and cooks and another thing to botanists. You and I and Julia Child classify things by their qualities in cooking and eating; botanists classify them by… different criteria, to do with form and function in nature (not in the pot). In botany, a banana is a berry and a strawberry is not. This does not mean that “a banana is really a berry and a strawberry really isn’t a berry wow can you believe it!!!!!!” Botany just came to use existing words in reconfigured senses rather than coming up with new words; they determined that consistency of sense in certain qualities was important and in other qualities was unimportant, and you and I and Julia have different priorities. Anyway, a pistachio is not a nut, botanically. It’s a seed. It’s in the middle of a fruit – specifically a drupe (cherries are also drupes). We don’t eat the fruit. We don’t eat the whole seed. We just eat the soft part in the middle of the seed. (Which, incidentally, gets very soft indeed if you cook it.)
How do the seeds get half-open, by the way? They just pop open at a certain stage in ripeness. Pop! They dehisce. “De-hiss?” Well, popping is quite the opposite of hissing… Dehisce means ‘open up’. It can also mean ‘doff your clothes’. Which can itself get a little seedy but never mind.
But never mind the sound of popping and of not hissing. What is the sound of pistachio?
This may seem obvious, as you probably say it the same way all your friends say it. But it has been a bit of an issue for me for some time. You see the word looks like an Italian word, and if it’s Italian, the ch is pronounced “k.” So “pi sta ki o.” But no. You almost certainly say it “pistashy-o.” But you may say it “pistatchy-o” if you’re British. So what’s up? What do the Italians say?
The Italians spell it pistacchio, with two c’s. And say it “pi stak ki o.” Well, they do in standard Italian now. But this word has been in English since the 1400s, and it came in by way of French as much as Italian. French for pistachio is pistache, though in earlier times there has also been a pistace version. And in Italian? Well, there’s the modern form, and there’s the regional variant pistacio, which in standard Italian would be said “pi sta chi o” (i.e., /pi.ˈsta.tʃi.o/), though I can’t say how the regional dialects say it.
But where did all that come from? Latin pistacium. Which in the medieval style says “ch” for the c but in classical style says “k.” However, the genus name – also “Latin” but botanical Latin, which means a special-use version of Latin no one has ever made complete Latin sentences with – is Pistacia.
Right, so OK, where did Latin get it from? Greek πιστάκιον pistakion. And Greek got it probably from Farsi pistah or Pahlavi pistag, and perhaps ultimately from Aramaic pistqa. So there we have it. A uvular stop /q/, then velar stops /k/ and velar or glottal fricatives /h/. And over time it moves forwards in the mouth and gradually softens, through affricate /tʃ/ to fricative /ʃ/.
So does that mean the correct pronunciation is “pi sta ki o”? Not in English. Just as pistachios soften with time in the cooking pot, that last consonant in pistachio has softened with time going from language to language. But whereas it has moved forward in the mouth, what it names tends to move back in the mouth as you chew and swallow it. And then, of course, you reach for the next one.