This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鵃 combines 舟 (boat) and 鳥 (bird), but the exact historical development and original meaning are uncertain.
A boat 舟 and a bird 鳥 together suggest a bird associated with boats, but the exact meaning is unclear.
For チュウ, imagine a bird on a boat making a soft 'chew' sound as it pecks at the wood: chew -> チュウ.
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