This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
蟉 combines 虫 (insect) with 翏, which likely contributes the sound. The exact historical development is uncertain.
With 虫 on the left, 蟉 likely relates to some kind of insect or worm, but its specific meaning is unknown.
For リュウ, imagine a rare insect named Ryu: Ryu -> リュウ, and the insect 虫 is part of 蟉.
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