This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 矦 is uncertain. It may be an ancient variant or a character with limited modern use.
The outer enclosure 厃 looks like a cliff or overhang, and inside is 矢 (arrow). Picture an arrow stuck under a cliff, its purpose unknown.
For コウ, imagine a mysterious arrow under a cliff that makes a hollow 'koh' sound when the wind blows: koh -> コウ.
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