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Olefin (also known as polyolefin and polypropylene)
A manufactured fiber characterized by its light weight, high strength, and abrasion resistance. Olefin is also good at transporting moisture, creating a wicking action. End-uses include activewear apparel, rope, indoor-outdoor carpets, lawn furniture, and upholstery.

Organdy
A stiffened, sheer, lightweight plain weave fabric, with a medium to high yarn count. End-uses include blouses, dresses, and curtains/draperies.

Organza
A crisp, sheer, lightweight plain weave fabric, with a medium to high yarn count , made of silk, rayon, nylon, or polyester. The fabric is used primarily in evening and wedding apparel for women.

Osnaburg
A tough medium to heavyweight coarsely woven plain weave fabric, usually made of a cotton or cotton/poly blend. Lower grades of the unfinished fabric are used for such industrial purposes as bags, sacks, pipe coverings. Higher grades of finished osnaburg can be found in mattress ticking, slipcovers, workwear, and apparel.

Ottoman
A tightly woven plain weave ribbed fabric with a hard slightly lustered surface. The ribbed effect is created by weaving a finer silk or manufactured warp yarn with a heavier filler yarn, usually made of cotton, wool, or waste yarn. In the construction, the heavier filler yarn is completely covered by the warp yarn, thus creating the ribbed effect. End uses for this fabric include coats, suits, dresses, upholstery, and draperies.

Oxford
A fine, soft, lightweight woven cotton or blended with manufactured fibers in a 2 x 1 basket weave variation of the plain weave construction. The fabric is used primarily in shirtings.