This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
橎 combines 木 (tree/wood) with 番, which likely contributes the sound. The exact historical development is uncertain.
The left side is 木 (tree), and the right side is 番 (number/turn). Imagine a tree with numbered branches, but its meaning remains uncertain.
For ハン, picture a hand (ハン sounds like 'hand' without the 'd') reaching out to touch the mysterious tree: hand -> ハン.
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