Sportswear has been called America's main contribution to the history of fashion design, developed to cater to the needs of the increasingly fast-paced lifestyle of American women. The term started out as a fashion industry term describing informal and interchangeable separates (i.e., blouses, shirts, skirts and shorts), and in the 1920s became a popular descriptive term for relaxed, casual wear typically worn for spectator sports. Since the 1930s the term has been used to describe both day and evening fashions of varying degrees of formality that demonstrate this relaxed approach while remaining appropriate wear for many business or social occasions.
The term can also refer to activewear, which is clothing designed specifically for participants in sporting pursuits.
The early sportswear designers were associated with ready-to-wear manufacturers, rather than haute couture houses. The clothes were intended to be washable and easy to care for, with accessible practical fastenings to enable the modern, increasingly emancipated woman to dress herself without a maid's assistance. While most fashions in America in the early 20th century were directly copied from Paris, designer sportswear was the exception to this rule, being an entirely home-grown invention.