Eli-
Marian and I are both saying the same thing. Fabric and fiber are different. When you describe the material (fabric) that your dress is made from you need to name both the "weave" or construction of the "fabric" and the "fiber" that it is made from. Linen, rayon, cotton, and flax, etc. are fibers; burlap, hopsacking, chintz, and velvet, etc. are fabrics.