Pronunciation:
[span-deks]

 
Origin:
1959; American English, an alteration of "expand"

Definition:
A manufactured fiber in which the fiber-forming substance is a long chain synthetic polymer composed of at least 85% of a segmented polyurethane. Spandex is lighter in weight, more durable, and more supple than conventional elastic threads and has between two and three times their restraining power. It can be repeatedly stretched over 500% without breaking and still recovers instantly to its original length. It does not suffer deterioration from oxidation as is the case with fine sizes of rubber thread, and it is not damaged by body oils, perspiration, lotions, or detergents.