place name
鄲 is a kanji used primarily in proper nouns, especially historical Chinese place names. Its standalone meaning is simply 'place name'.
鄲 combines the city wall radical ⻏ with 單, which likely provides the sound. It was used to write the name of the ancient Chinese city of Handan.
The city wall radical ⻏ on the right suggests a place, and the left side 單 gives the sound. Together they mark a specific place name.
For タン, imagine a tan-colored wall surrounding the ancient city: tan -> タン, and the wall marks the place.
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