any object that sticks in throat, bony
骾 centers on something hard and bony that obstructs or sticks, especially in the throat. The idea of a bone-like object causing blockage connects the given meanings.
骾 combines 骨 (bone) with 更, which likely contributes a phonetic element. The character suggests a bone or bony object that causes obstruction.
The left side 骨 means bone, and the right side 更 can suggest change or again. Imagine a bone that gets stuck in your throat again and again—a bony obstruction.
For コウ, picture a bone stuck in your throat making you cough: cough -> コウ, and the bony object causes the coughing.
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