Old English didn't use the words left and right for the two hands. Instead, it used winestre and swiþre: ‘friendlier’ and ‘stronger.’

But ‘friendlier’ wasn’t a compliment. It was a superstitious euphemism. The left side was considered unlucky and dangerous, so you called it something nice to keep it from harming you.

Across European languages, words for ‘left’ are strikingly unstable, constantly being replaced as each new term absorbs the old stigma. Latin sinister just meant ‘left’ before it meant ‘evil.’ The word keeps going bad, and speakers keep reaching for a fresh euphemism.

Ancient Greek did something similar to Old English, calling the left side aristeros, ‘the better one.’ Even Latin sinister likely originated in a word meaning ‘more advantageous.’

This process is called taboo avoidance: the same impulse that makes people say the good folk instead of naming the fairies.

You give something a nice name precisely because you’re afraid of it.