This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
銙 combines 金 (metal) with 夸, which likely contributes the sound. The exact historical development is uncertain.
The left side is metal 金, and the right side 夸 looks like a person with a big head and arms. Picture a metal ornament shaped like a person, but its exact meaning is uncertain.
For カ, imagine a metal car (カ) ornament: car -> カ, and the metal 金 component reinforces the image.
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