Dacron (dā`krŏn, dăk`rŏn), trademark for a polyester fiber. Dacron is a condensation polymer obtained from ethylene glycol and terephthalic acid. Its properties include high tensile strength, high resistance to stretching, both wet and dry, and good resistance to degradation by chemical bleaches and to abrasion. The continuous filament yarn is used in curtains, dress fabrics, high-pressure fire hoses, men's shirts, and thread. The staple fiber is ideal for mixing with wool in men's and women's suits, as well as in dress fabrics, knitted wear, and washable woven sportswear.