This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
螅 combines 虫 (insect) with 息, which likely contributes the sound. The exact historical development is uncertain.
The insect radical 虫 beside 息 suggests a creature related to breathing or resting, but the exact meaning is unclear.
For シ, imagine a tiny insect sighing: the sigh sound cues シ while the insect rests on a leaf.
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