kind of herb
芎 refers to a specific kind of herb, with no broader abstract extensions beyond that botanical sense.
芎 combines the plant radical 艹 with 弓, which likely contributes a phonetic element. The exact historical development is uncertain.
The plant radical 艹 sits above 弓, like a bow-shaped herb. Picture a curved, bow-like stalk of a medicinal plant.
For キュウ, imagine a bow-shaped herb that cures you: the herb's shape is like a bow, and it cures you — cure you -> キュウ.
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