The Collaborative International Dictionary of English v.0.48:

Rickrack \Rick"rack`\, n.
   A kind of openwork edging made of serpentine braid.
   [1913 Webster]

WordNet (r) 3.0 (2006):

rickrack
    n 1: a narrow zigzag ribbon used as trimming [syn: rickrack,
         ricrac]