name of a river in Henan, Henan
汴 is a proper noun referring to a river in Henan province and, by extension, the region itself. Its meaning is tied to that specific geographic name rather than a general concept.
汴 is a phono-semantic compound: 氵 (water) indicates a river, and 卞 (ヘン) gives the sound. It was created as a specific place name for the Bian River.
The water radical 氵 beside 卞 points to a river. Think of 汴 as the name of a specific river flowing through Henan.
For ヘン, picture a hen standing by the river: hen -> ヘン, and the hen is at the Bian River in Henan.
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