This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
碝 combines 石 (stone) with 耎, which likely contributes the sound. The exact historical development is uncertain.
The left side is stone 石, and the right side 耎 looks like a soft, yielding shape. Imagine a stone that is surprisingly soft or crumbly, but its true meaning is unclear.
For ゼン, picture a Zen garden stone: Zen -> ゼン, and the stone 石 sits quietly in the garden.
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