This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
骬 combines 骨 (bone) with 于, but the exact historical development and original meaning are uncertain.
The left side 骨 means bone, and the right side 于 looks like a hook or a bent shape. Picture a hooked bone, but its exact meaning is unclear.
For ウ, imagine a bone-shaped hook making a soft 'oo' sound when you tap it: 'oo' -> ウ.
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