Hi, new mod here! I’m Luke (most of you already know me), and today we’re talking about something quite romantic, so break out the jazz music and candles. For those of you not familiar with the Swadesh list, it’s basically a list of words that are unlikely enough to be borrowed from language to language to be used as a means to compare whether languages have historical links to each other (this is where you start making out, by the way).
One of the words on this list is “heart”. Switch over to Classical Persian, and we have the word “dil” (Iranian “del”). Let’s be frank, these words don’t look related at all. Maybe one language went through semantic drift and had a formerly unrelated word take on the meaning “heart”? However, they are in fact related to each other, and I’m going to be talking about how they both came to their modern forms from PIE.
First off: for those who didn’t know, Persian is an Indo-European language, and Arabic is a Semitic language. In other words: PERSIAN IS UNRELATED TO ARABIC, and if you believe this you’re lucky I haven’t hunted you down yet.
Now, PIE. The PIE root for “heart” is *ḱerd. Or *ḱr̥d, it’s confusing. Probably the first thing you notice about this word is the k with an accent over it: how the hell is one supposed to pronounce that? The answer is, as is the answer to many questions regarding PIE’s phonology, “we don’t quite know”. By far the most accepted theory is that it’s produced using the soft palate in some fashion, the same area where the sound “y” is produced, and therefore called “palatal”.
In PIE, there were actually 3 kinds of “k” like sounds: palatal *ḱ, plain *k, and labial *kʷ, and these “k”-like sounds are the source of one of IE’s oldest splits, the satem-centum split. In satem languages, named after the Avestan word for “hundred”, satəm, the plain and labial velars merged together while the palatal developed into different sounds. The Indo-Iranian languages, the family containing Persian, Hindi, and many others, are all satem. However in centum languages, including Germanic among others and named after the Latin word “centum” which also means “hundred”, the palatal and plain consonants merged and the labial velars developed separately.
With that background information out of the way, we can go back to *ḱerd. Keeping in mind the satem-centum split, we know that we would have something like *kerd, which still wouldn’t account for the “h” in all modern Germanic languages. That is explained by Grimm’s law, a change in which *p t k became something like “f th x”, while *b d g became “p t k”. Applying Grimm’s law, we eventually get Proto-Germanic *hertōn (according to Leiden’s “Etymological Dictionary of Proto-Germanic”) and subsequently “heart”.
Now it’s time to turn to *ḱr̥d and move our eyes away from continental Europe. Proto-Indo-Iranian regularly turns *ḱ into *ĉ, which would give us PII *čr̥d. This would be true if God didn’t hate us, which he unfortunately seems to. You see, for some goddamn reason *ḱr̥d became *ĵʰr̥ dayam, and that *ĵʰ became Proto-Iranian *ź, which led to multiple different sounds depending on the language. In most Iranian languages it became *z, while in the Southwest Iranian branch, which includes Persian, it became *d instead.
So the “d” in “dil” makes sense, but what about the “l”? One hallmark feature of PII is the merging of *l and *l̥ into *r and *r̥. The lack of any sort of “L” sound led to it being redeveloped in various Indo-Iranian languages; Persian did this by reducing the cluster *rd to “l”. One can see the original *rd cluster (or something closer to it) preserved in other Iranian languages’ words for “heart”, including Balochi “zird” or Pashto “zṛə”. Now *ḱr̥d leading to “dil” doesn’t seem so far-fetched, does it?
So yes, “heart” and “dil” are in fact related, to answer a question that I can’t imagine many people before me have asked. If there’s anything to take out of this, it’s that PERSIAN IS INDO-EUROPEAN AND NOT RELATED TO ARABIC.