the French word for 'yes'.
From Old French 'oui' which evolved from Latin 'hoc ille' meaning 'that he/it [agrees]'. Through sound changes, this phrase contracted into the single word 'oui' we know today.
The fascinating thing about 'oui' is that it literally came from a whole phrase that just got smooshed together over centuries—'hoc ille' eventually became one sound, which is how lots of modern words are born!
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