county in Henan province, surname
郟 is a rare kanji used primarily as a proper noun: a historical county in Henan province and a surname. Its standalone meaning is tied to that place and family name.
郟 combines 夾 (to press from both sides) with the city enclosure ⻏, suggesting a place name. The exact historical development is uncertain, but it likely originated as a geographical designation.
The left side 夾 looks like a person pressing things together, and the right side ⻏ is a city wall. Picture a county in Henan where people are squeezed between the city walls, or a family name that originated there.
For コウ, imagine a county official named Kou (こう) stamping documents inside the city walls: Kou -> コウ.
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