This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鱰 is a kokuji (Japanese-made kanji) combining 魚 (fish) with 署, likely chosen for its sound to represent the fish しいら (mahi-mahi).
The fish radical 魚 suggests a fish, and the right side 署 may hint at the sound. Picture a fish with a name tag reading '署' to remember it's the しいら fish.
For しいら, imagine a fish saying 'Shee-ra!' as it leaps from the water: 'Shee-ra' cues しいら, and the fish radical 魚 confirms it's a fish.
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