paper, label, letter, composition
牋 centers on written documents: paper, labels, letters, or compositions. It refers to physical or textual items used for recording or communicating information.
牋 combines 片 (a split piece of wood, often used for writing tablets) with 戔, which likely contributes the sound. Together they suggest a wooden tablet for writing, extended to paper and documents.
The left side 片 looks like a flat writing surface, and the right side 戔 resembles stacked papers. Imagine a wooden tablet covered with labels and letters.
For セン, picture a thousand (千, せん) sheets of paper stacked on the left tablet: 千 -> セン, and the whole stack becomes a composition.
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