inlaid shell-work
蜔 refers to decorative inlaid shell-work, a specific craft technique where shell pieces are set into a surface to create patterns.
蜔 combines the insect radical 虫 with 甸, which likely contributes the sound. The exact historical development is uncertain, but the character is associated with shell inlay work.
The insect radical 虫 hints at small creatures like shellfish, and the right side 甸 looks like a field 田 wrapped in a covering 勹. Imagine tiny shell pieces being arranged in a field-like pattern to create inlaid artwork.
For テン, picture ten (テン) tiny shell pieces being inlaid into a wooden surface: ten -> テン, and each piece fits perfectly into the design.
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