splashed pattern dyeing or weaving
緕 centers on a textile technique where threads are resist-dyed before weaving to create a blurred, splashed pattern. The meaning is specific to this kasuri dyeing or weaving process.
緕 combines 糸 (thread) with 斉, which likely contributes a phonetic element. The character is a relatively modern Japanese kokuji created to represent the kasuri textile technique.
The thread radical 糸 beside 斉 suggests threads being arranged or aligned for the resist-dyeing process. Imagine threads tied and dyed, then woven to reveal a splashed pattern.
For かすり, picture a piece of kasuri fabric with a blurred pattern that looks like a 'castle' (かす) in the mist, and you 'reel' (り) in the thread to weave it: かすり.
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