资料来源 : Webster's Revised Unabridged Dictionary (1913)

Blanket stitch \Blanket stitch\
   A buttonhole stitch worked wide apart on the edge of
   material, as blankets, too thick to hem.

资料来源 : WordNet®

blanket stitch
     n : strong reinforcing stitch for edges of blanket and other
         thick material; similar to buttonhole stitch