cramps
痃 centers on muscle cramps: sudden, painful, involuntary contractions.
痃 combines the sickness radical 疒 with 玄, which likely contributes the sound. The exact historical development is uncertain.
The sickness enclosure 疒 wraps around 玄, like a mysterious dark knot of pain. Picture a sudden cramp tightening like a twisted cord inside the body.
For ゲン, imagine a cramp so severe it makes you say 'Gen!' (like a sharp, involuntary grunt). The sound 'Gen' cues ゲン while the pain knots up your muscles.
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