This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 閺 is uncertain. It combines 門 (gate) with 旻, but the original meaning and component function are unclear.
With no clear meaning, picture a mysterious gate 門 enclosing an unknown symbol 旻. The gate hides something uncertain.
For ベン, imagine a bent gate 門 that won't close properly: bent -> ベン, and the gate remains slightly open.
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