体裁
ていさい · teisai · JLPT N1 · noun
style
👔 体 body + 裁 cut (tailoring): garment cut to fit the body = form, appearance
Decency comes from the same idea: clothes cut to fit the body look proper. So 体裁 covers form, style and respectable appearance, and a text with good 体裁 is shaped to fit its purpose.
裁 — 戈 (halberd) + 𢦏 (phonetic, to cut)
裁 originally depicted cutting cloth with a blade, combining 衣 (clothing, embedded in the character) with 𢦏 as the phonetic component suggesting cutting. The core meaning 'to cut cloth' extended to tailoring, then broadly to 'judge, decide, reduce' — as in deciding by cutting away. Modern uses include 裁判 (judge) and 裁缝 (tailor).