The Collaborative International Dictionary
Blanket stitch
Blanket stitch \Blanket stitch\ A buttonhole stitch worked wide apart on the edge of material, as blankets, too thick to hem.
Wiktionary
blanket stitch
n. 1 (context sewing English) A strong stitch, similar to a buttonhole stitch, used to finish and reinforce the edges of blankets etc. 2 A similar, more decorative stitch.
WordNet
blanket stitch
n. strong reinforcing stitch for edges of blanket and other thick material; similar to buttonhole stitch
Wikipedia
Blanket stitch
__NOTOC__ The blanket stitch is a stitch used to reinforce the edge of thick materials. Depending on circumstances, it may also be called a whip stitch or a crochet stitch. It is defined as "A decorative stitch used to finish an unhemmed blanket. The stitch can be seen on both sides of the blanket."