Merriam-Webster Collegiate Dictionary - purl

 I. noun  Etymology: Middle English  Date: 14th century  1. gold or silver thread or wire for embroidering or edging  2. the intertwisting of thread that knots a stitch usually along an edge  3. ~ stitch  II. verb  Date: 1526  transitive verb  1.  a. to embroider with gold or silver thread  b. to edge or border with gold or silver embroidery  2. to knit in ~ stitch  intransitive verb to do knitting in ~ stitch  III. noun  Etymology: perhaps of Scandinavian origin; akin to Norwegian ~a to ripple  Date: circa 1522  1. a ~ing or swirling stream or rill  2. a gentle murmur or movement (as of ~ing water)  IV. intransitive verb  Date: 1591  1. eddy, swirl  2. to make a soft murmuring sound like that of a ~ing stream