This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
橾 combines 木 (tree/wood) with 喿, which likely contributes a phonetic element. The exact historical development and original meaning are uncertain.
With 木 on the left, 橾 might relate to a wooden object or tool, but its meaning is unclear. Picture an old, mysterious wooden artifact whose purpose has been forgotten.
For シュ, imagine a shoe made of wood: shoe -> シュ, and the wooden shoe is this mysterious 橾.
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