This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
苆 is a rare character. It visually combines the grass radical 艹 with 切, but its historical origin and original meaning are uncertain.
The grass radical 艹 sits above 切 (cut). Imagine cutting grass, but the kanji's actual meaning is unclear.
For すさ, picture cutting grass (苆) and making a soft rustling sound: すさ (susa) is the sound of the grass being cut.
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