This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 魸 is uncertain. It visually combines 魚 (fish) with 片, but the component relationship is unclear.
The left side is a fish 魚, and the right side is a fragment 片. Picture a rare, fragmentary fish that is hard to identify—its meaning is uncertain.
For ナマズ, imagine a catfish (ナマズ) made of fish parts and fragments: the whole reading ナマズ is tied to the fish shape.
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