The Collaborative International Dictionary of English v.0.48:

Burlap \Bur"lap\, n.
   A coarse fabric, made of jute or hemp, used for bagging;
   also, a finer variety of similar material, used for curtains,
   etc. [Written also burlaps.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

burlap
    n 1: coarse jute fabric [syn: burlap, gunny]