An Old English letter (ƿ) that represented the 'w' sound and was eventually replaced by the modern letter 'w' or the double 'u' combination.
From Old English wynn, meaning 'joy' or 'delight.' The letter itself was named after the word for joy because Old English scribes considered it a pleasant letter to write. It fell out of use after the Norman Conquest.
The wynn letter shows how writing systems evolve—it was abandoned simply because Norman French scribes didn't recognize it and started using 'uu' (which became 'w') instead. Some modern fonts and games bring it back for aesthetic reasons!
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