name of Chinese river
渮 is a rare kanji used in the name of a Chinese river. Its standalone meaning is tied to that specific geographical name and has no broader conceptual center.
渮 combines 氵 (water) with 苛, likely as a phono-semantic compound for a river name. The exact historical development is uncertain.
The water radical 氵 beside 苛 suggests a river whose name sounds like 苛. Picture a map with a river labeled in a way that echoes the right side.
For カ, imagine a car driving along the bank of this Chinese river: car -> カ, and the river flows beside it.
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