foreshore reclaimed from river
潏 centers on land reclaimed from a river, specifically a foreshore area that has been built up or drained for use. The meaning is narrow and technical, referring to this specific type of reclaimed riverbank.
潏 combines the water radical 氵 with 矞, which likely contributes a phonetic element. The exact historical development is uncertain, but the character is associated with water-related land reclamation.
The water radical 氵 suggests a river, and the right side 矞 looks like a complex structure built on the bank. Picture a reclaimed foreshore where the river has been pushed back to create usable land.
For ケツ, imagine a construction crew reclaiming land by the river, and they need to use a lot of kets (a made-up word for heavy machinery) to move the earth: kets -> ケツ.
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