Ishikiate is a square piece of thick cloth for the reinforcement of an unlined garment; it prevents the seams from coming apart and is applied from the back (inside) to the part that presses against the wearer's hip.
居敷当（いしきあて）は、単衣仕立ての衣の尻が当たるあたりに、背縫い目が開かないように補強のために裏（中）から当てる四角い厚地の布片である。