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origin; beginning
variable measure of fabric (28.8 cm in width); for kimonos: at least 10 m in length; for haori: at least 7.27 m in length; for other clothes: at least 6.06 m in length
tip; extremity
「端」 has other readings with different meanings.
事件の発端は些細な誤解だった。
The origin of the incident was a trivial misunderstanding.
研究の端を開いたのは一通の手紙だ。
What opened the beginning of the research was one letter.
彼女が口を開いたことが議論の端となった。
Her speaking up became the beginning of the discussion.