cord to hold up sleeves, (kokuji)
襷 refers to a specific traditional Japanese cord used to hold up kimono sleeves while working. It is a kokuji, created in Japan for this culturally specific item.
襷 is a Japanese kokuji, combining the clothing radical 衤 with 擧 (raise), suggesting a cord used to raise or hold up sleeves.
The left side 衤 is clothing, and the right side 擧 suggests lifting. Picture a cord lifting the sleeves of a kimono so the wearer can work freely.
For たすき, imagine a task-ease key: the cord makes tasks easier, so 'task-ease key' -> たすき.
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