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decorative string used to hold a kimono sash in place
帯締めをしっかり結んだ。
I tied the obi cord tightly.
着物に合う帯締めをお勧めします。
I'll recommend an obi cord that matches your kimono.
華やかな帯締めが着物姿を一層引き立てます。
A gorgeous obi cord further sets off the kimono outfit.