kneecap
髕 centers on the kneecap, the small bone at the front of the knee joint.
髕 combines 骨 (bone) with 賓, which likely contributes the sound ヒン. The character specifically denotes the kneecap bone.
The left side 骨 means bone, and the right side 賓 looks like a guest under a roof. Imagine a guest kneeling, putting pressure on the kneecap bone.
For ヒン, picture a hinged kneecap: the hinge sound cues ヒン, and the bone 骨 on the left reminds you it's the kneecap.
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