drooping leaves, fringe soft, delicate
蕤 centers on soft, drooping plant parts: leaves that hang down delicately, or a fringe-like softness. The idea extends to anything delicate or softly hanging.
蕤 combines the grass radical 艹 with 甤, which likely contributes the sound and the idea of drooping or hanging growth. The exact historical development of 甤 is uncertain.
The grass top 艹 sits above 甤, which looks like a pig 豕 under a growing plant 生. Picture a pig brushing against soft, drooping leaves that hang down like a delicate fringe.
For ニ, imagine a knee-high plant with drooping leaves: knee -> ニ, and the soft leaves brush your knee as you walk past.
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