white hempen cloth worn by mourn
絰 centers on a specific type of mourning garment: white hempen cloth worn during funeral rites. Its meaning is narrow and culturally specific.
絰 combines 糸 (thread, cloth) with 至, which likely contributes a phonetic element. The character specifically denotes hempen mourning cloth.
The left side 糸 represents cloth, and the right side 至 can be thought of as reaching the end. Picture reaching the end of life, wrapped in white hempen mourning cloth.
For テツ, imagine the sound of tearing cloth: 'tets' as the hempen fabric is torn for mourning. Tets -> テツ.
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