cup
墫 centers on a cup or drinking vessel, likely a specific type of cup or goblet.
墫 combines 土 (earth, clay) with 尊, which likely contributes the sound and may relate to a vessel. The exact historical development is uncertain.
The left side 土 suggests clay, and the right side 尊 looks like a container. Picture a clay cup or goblet made from earth.
For シュン, imagine a shiny new cup: shiny -> シュン, and the cup is made of clay.
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