This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
癋 combines 疒 (sickness) with 惡, but the exact historical development and original meaning are uncertain.
The sickness enclosure 疒 wraps around 惡 (bad, evil), suggesting a severe or evil illness, but the actual meaning is unclear.
For カク, imagine a harsh, hacking cough coming from the sickness enclosure: hack -> カク, as the evil illness takes hold.
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