This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
巑 combines 山 (mountain) with 贊, which likely contributes the sound. The exact historical development is uncertain.
The left side is a mountain 山, and the right side 贊 is a complex shape. Without a clear meaning, picture a mysterious mountain peak with a name that sounds like サン.
For サン, imagine the sun rising over the mountain: sun -> サン, and the mountain 山 on the left reinforces the scene.
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