Understitch (stitch in a ditch)
Understitching serves the purpose of stitching the seam allowance to the garment underside so that the lining or facing remains on the inside of the garment. This is achieved through a process of trimming the seam allowances with a gradation and then stitching only though the underside facing or lining and the seam allowances, thus the stitching line is not visible on the outside of the garment. It is commonly found along necklines and sleeveless arm scyes.
Contributed by community member melodym