This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
緢 combines the thread radical 糸 with 苗, which likely contributes a sound element. The exact historical development and original meaning are uncertain.
With 糸 (thread) and 苗 (seedling), imagine delicate silk threads wrapped around young seedlings, but the true meaning is unclear.
For ボウ, picture a bow made of silk thread tied around a seedling: bow -> ボウ, though the kanji's meaning is uncertain.
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