This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
苤 combines the plant radical 艹 with 丕, but the exact historical development and original meaning are uncertain.
The top is the plant radical 艹, and the bottom is 丕, which looks like a sprout pushing through the ground. Picture a rare, unnamed plant whose meaning is still unknown.
For ヒ, imagine a tiny plant whispering 'hee' as it sprouts: hee -> ヒ, the sound of a mysterious new growth.
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