striped, poisonous fly
螌 centers on a specific kind of poisonous insect: a striped, venomous fly. The meanings are tightly linked to this creature.
螌 combines 虫 (insect) with 般, which likely contributes the sound. The character was created to name a specific poisonous fly.
The bottom 虫 is an insect, and the top 般 looks like a boat or a general shape. Imagine a striped, poisonous fly buzzing around a boat, its venomous sting dangerous to those on board.
For ハン, picture a hand swatting at the poisonous fly: hand -> ハン, and the fly dodges the hand.
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