Overcast is a needlework technique which involves making small in and out stitches with the purpose of tightly join two fabric pieces together. This technique adds strength and prevents the material from fraying. The whipstitch is used
for a variety of stitching projects, like finishing the edge, sewing appliques, or even making coverlets. It offers a tidy and expert look for the final piece.
Every whipstitch definition in American English