heorte

The Proto-Indo-European root *ḱḗr (also reconstructed as *ḱerd-) meant 'heart' at least 6,000 years ago. It produced Latin cor (stem cord-), Greek kardia, Sanskrit hṛd, Armenian sirt, Lithuanian širdis, and Old English heorte. The survival rate is extraordinary. Most PIE roots left traces in only a few daughter languages. This one left traces in nearly all of them.

Old English heorte became Middle English herte, then modern heart. The spelling with 'ea' was fixed by early printers, though the pronunciation had already shortened the vowel. The word has meant the physical organ and the seat of emotion for as long as records exist — Anglo-Saxon poetry made no distinction. In Beowulf, the heorte is where courage lives.

Latin cor gave English cordial (from the heart), courage (originally 'heart-ness,' via French corage), and record (originally 'to pass back through the heart,' i.e., to memorize). Greek kardia gave cardiac, cardiology, and the prefix cardio-. The same 6,000-year-old root is in your doctor's vocabulary and your gym's workout schedule.

The heart-as-emotion metaphor is not universal. In many languages, the liver or the stomach is the seat of feeling. But in the Indo-European family, the heart won that role early and kept it. The emoji, the Valentine, the hand-on-chest gesture — all of these trace back to a metaphor that was old when Homer was young.