This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The historical origin of 𨺉 is uncertain. It visually contains the mound radical ⻖ on the left and a right side combining 木 and 爪, but the exact development is unclear.
The kanji has no clear meaning, so a mnemonic is not possible.
For さい, imagine a sigh (さい) of frustration when encountering a rare kanji with no meaning: sigh -> さい.
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