This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
潓 combines 氵 (water) with 惠, which likely contributes sound. The exact historical development is uncertain.
The water radical 氵 beside 惠 suggests something related to water, but the exact meaning is unclear. Imagine a rare water spirit named 潓 that appears only in old texts.
For ケイ, imagine a kayak gliding on the water: kayak -> ケイ, and the water radical 氵 reinforces the scene.
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