fine, slender, thin kimono
纖 centers on extreme thinness and delicacy: something fine, slender, or light like a thin kimono. The idea is of thread-like fineness.
纖 combines 糸 (thread) with 韱, which likely contributes the sound and the idea of smallness or fineness. The character expresses the concept of thread-like thinness.
The left side 糸 is thread, and the right side 韱 looks like a complex, delicate structure. Imagine a single fine thread woven into an intricate, slender pattern: 纖 is anything as fine and thin as that thread.
For セン, picture a thin, fine sen (銭, a small coin) balanced on a delicate thread: sen -> セン, and the coin is as slender as the thread itself.
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