Duck. [From Swed. duk, cloth] A strong linen fabric, plain-woven, without twill, lighter than canvas, and used for small sails, tents, and for men's summer clothing; in color usually white or unbleached, but sometimes dyed in plain colors. Cotton duck is made in imitation of the original linen, and is always distinguished by being woven with a double warp; used for men's overalls, tents, awnings, etc. The quality is denoted like denim by the weight of the cloth in ounces per square yard. Russia duck is a white linen canvas of fine quality.