This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 鷠 is uncertain. It visually combines 魚 (fish) and 鳥 (bird), but the original intent is unclear.
The kanji shows a fish 魚 beside a bird 鳥, but its meaning is unknown. Picture a strange creature that is half fish, half bird, representing something mysterious.
For ギョ, imagine a fish 魚 (ぎょ) trying to fly like a bird 鳥: the fish's reading ぎょ cues ギョ, even though the kanji's meaning is unclear.
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