英語候補small opening in the side of some traditional Japanese clothing (located where the sleeve meets the bodice, below the armpit)
詰め袖つめそでkimono with completely attached sleeves (i.e. lacking an opening on the side under the armpit)
脇明けわきあけclothing with such an opening (usu. worn by women or children)robe worn by military officials with a round collar, unstitched open sides, and no wrapped fabric along the bottom