This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
蛧 combines 虫 (insect) with 网 (net). The exact historical development is uncertain, but it likely originally referred to a type of insect or a net-related concept.
The insect radical 虫 beside a net 网 suggests an insect caught in a web or net, but the actual meaning is unclear.
For ボウ, imagine a bow-shaped net catching an insect: bow -> ボウ, and the insect is trapped in the net.
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