jaundice
癀 centers on jaundice, a condition that turns the skin and eyes yellow.
癀 combines 疒 (sickness) with 黄 (yellow), likely expressing a disease characterized by yellow discoloration.
The sickness enclosure 疒 wraps around 黄 (yellow). Picture a sick person whose skin turns yellow: that is jaundice.
For コウ, imagine a person with jaundice coughing yellow dust: cough -> コウ, and the yellow color spreads.
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