This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 鵣 is uncertain. It visually combines 束 and 鳥, but the original semantic or phonetic role of these components is unclear.
No clear meaning is known, so a mnemonic is not possible.
For ライ, imagine a rare bird tied with a bundle (束) that cries out 'lie!' because its meaning is uncertain: lie -> ライ.
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