This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
璻 combines 王 (jade) with 翠, which likely contributes sound. The exact historical development is uncertain.
The 王 (jade) radical suggests a connection to precious stones, and 翠 is associated with kingfisher feathers or green-blue colors. Picture a rare jade ornament with the iridescent sheen of a kingfisher's plumage.
For スイ, imagine a kingfisher (翠) swooping down to snatch a jade (王) ring: swoop -> スイ, and the bird's swift motion helps recall the reading.
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