This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
汯 combines 氵 (water) with 厷, which likely contributes a phonetic element. The exact historical development and original meaning are uncertain.
With water 氵 on the left and 厷 on the right, imagine a deep, wide river whose name sounds like コウ, but its meaning remains unclear.
For コウ, picture a wide river flowing into a calm cove: cove -> コウ, even though the kanji's meaning is uncertain.
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