This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
襅 combines 衤 (clothing) with 畢, but the exact historical development and original meaning are uncertain.
The left side 衤 suggests clothing, and the right side 畢 is a complex shape. Without a clear meaning, picture a mysterious ceremonial robe with intricate patterns.
For ちはや, imagine a swift (はやい) warrior named Chi wearing this robe: Chi-ha-ya -> ちはや.
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