This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
箉 combines the bamboo radical 竹 with 拐, but the historical origin and meaning are uncertain.
With bamboo 竹 above 拐, imagine a bamboo tool shaped like a hook or used in a turning motion, but its exact purpose is unknown.
For カイ, picture a bamboo kite (カイト) made from the bamboo 竹 and the hooked shape 拐: kite -> カイ.
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