This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鄅 is a rare character combining 禹 and ⻏ (阝, the 'city' or 'mound' radical). It likely originated as a place name, but the exact historical development is uncertain.
The left side 禹 is a legendary figure associated with flood control, and the right side ⻏ suggests a place. Picture a forgotten ancient city named after Yu, its meaning lost to time.
For ウ, imagine the sound of wind (ウー) blowing through the ruins of that ancient city: ウー -> ウ.
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