This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
骿 combines 骨 (bone) with 并, which likely contributes the sound. The exact historical development is uncertain.
The left side 骨 suggests bone, and the right side 并 looks like two lines joined together. Imagine a rare bone condition where two bones are fused side by side.
For ヘン, picture a hen pecking at a strange bone: hen -> ヘン, and the bone is the 骨 part of 骿.
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