This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
柃 combines 木 (tree) with 令, which likely contributes a phonetic element. The exact historical development is uncertain, and the character is rare in modern Japanese.
With 木 (tree) on the left and 令 on the right, imagine a rare tree whose name sounds like レイ. Since the meaning is unclear, picture a mysterious tree marked with a 令 tag, waiting to be identified.
For レイ, imagine a ray of sunlight hitting the rare 柃 tree: ray -> レイ, and the tree stands out in the light.
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