This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 銯 is uncertain. It combines 金 (metal) and 糸 (thread), but the original purpose and meaning are unclear.
The kanji visually combines metal 金 and thread 糸, but no clear meaning emerges from these components alone.
For かすがい, imagine a metal clamp (かすがい) made of gold thread: かすがい is the reading, and the kanji shows metal and thread.
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