volume, chapter, book, editing, compilation
篇 centers on a structured written work: a volume, chapter, or book, and by extension the act of editing or compiling such a work.
篇 combines 竹 (bamboo) and 扁, which likely contributes the sound. Historically, bamboo strips were bound together to form books or chapters, so 竹 suggests the material of early written works.
The bamboo radical 竹 sits above 扁, like bamboo strips tied into a scroll. Imagine a stack of bamboo pages bound into a single volume or chapter.
For ヘン, picture a hen pecking at a bamboo book, turning the pages of a chapter: hen -> ヘン.
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