This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 宔 is uncertain. It visually combines 宀 (roof) and 主 (master), but the original meaning and component relationship are unclear.
With 宀 (roof) over 主 (master), imagine a master under a roof, but the kanji's meaning is uncertain, so treat it as a rare character with no clear definition.
For シュ, picture a shoe (シュ) placed under the roof (宀) by the master (主): shoe -> シュ.
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