The Collaborative International Dictionary of English v.0.48:

Quilt \Quilt\, v. t. [imp. & p. p. Quilted; p. pr. & vb. n.
   Quilting.]
   1. To stitch or sew together at frequent intervals, in order
      to confine in place the several layers of cloth and
      wadding of which a garment, comforter, etc., may be made;
      as, to quilt a coat. --Dryden.
      [1913 Webster]

   2. To wad, as a garment, with warm soft material.
      [1913 Webster]

   3. To stitch or sew in lines or patterns.
      [1913 Webster]

WordNet (r) 3.0 (2006):

quilted
    adj 1: made of layers of fabric held together by patterned
           stitching