Gymnasium, large room used and equipped for the performance of various sports. The history of the gymnasium dates back to ancient Greece, where the literal meaning of the Greek word gymnasion was “school for naked exercise.” The gymnasiums were of great significance to the ancient Greeks, and every important city had at least one. Usually built by the state, these grew from mere gathering places where exercises were performed to imposing structures with dressing rooms, baths, training quarters, and special areas for contests.

Originally, gymnasiums were public institutions where male athletes over age 18 received training for competition in the public games of that time (as opposed to the palaestrae, which were private schools where boys were trained in physical exercises). The supervision of the gymnasiums was entrusted to gymnasiarchs, who were public officials responsible for the conduct of sports and games at public festivals and who directed the schools and supervised the competitors. The gymnastai were the teachers, coaches, and trainers of the athletes. The Greek gymnasiums also held lectures and discussions on philosophy, literature, and music, and public libraries were nearby.

In German-speaking countries, the word Gymnasium refers to state-maintained secondary schools and is not associated with athletics or sports; Turnverein is used to designate a site for physical exercise. In English-speaking countries, however, the gymnasium has no connection with academic courses, and the term ordinarily designates a room or building for the practice of physical education. Outside the school system, the term was largely replaced in the late 20th century by the terms health club and fitness centre.