This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
皌 combines 白 (white) and 末 (tip, end). The exact historical development is uncertain, and no clear meaning is recorded.
With 白 (white) and 末 (tip), imagine the white tip of something, but since the meaning is unknown, treat this as a placeholder.
For バツ, imagine a white-tipped bat (バツ) flying at dusk. The bat's wing tips are white, linking the shape to the reading.
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