What is "satin stitch"

n. flat stitches worked so closely as to resemble satin

In sewing and embroidery, a satin stitch or damask stitch is a series of flat stitches that are used to completely cover a section of the background fabric. Narrow rows of satin stitch can be executed on a standard sewing machine using a zigzag stitch or a special satin stitch foot.

In order to maintain a smooth edge, shapes can be outlined with back, split or chain stitch before the entire shape including the outline is covered with satin stitch.

Machine-made satin stitch is often used to outline and attach appliques to the ground fabric.