yoke
胊 centers on a yoke, a wooden beam used to join animals for pulling. The meaning is narrow and concrete.
胊 combines the flesh radical ⺼ with 句, which may have contributed a phonetic element. The exact historical development is uncertain.
The flesh radical ⺼ suggests something related to the body, and 句 looks like a curved hook. Picture a yoke as a curved wooden beam resting on the flesh of an animal's shoulders.
For ク, imagine a cool yoke resting on an ox: cool -> ク, and the yoke keeps the animal steady.
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