Obi n. A sash, esp. the long belt-like broad sash of soft material worn by women aound the waist when wearing a traditional kimono, and usually having a large bow at the back. "Over this is bound the large sash (obi) which is the chief article of feminine adornment."
... of the pressure brought to bear by her grandfather, she had refused to wear the native garb, preferring the shabby garments she brought with her from America. I had never thought of her being Japanese; but that evening, when Page was announced and Zura walked into the room clothed in kimono and obi, my eyes were astonished with as fair a daughter of old Nippon as ever pompadoured her hair or ... — The House of the Misty Star - A Romance of Youth and Hope and Love in Old Japan • Fannie Caldwell Macaulay