The word gymnasium is the latinisation of the Greek noun γυμνάσιον (gymnasion), "gymnastic school", in pl. "bodily exercises" and generally "school", which in turn is derived from the common Greek adjective γυμνός (gymnos) meaning "naked", by way of the related verb γυμνάζω (gymnazo), whose meaning is "to train naked", "train in gymnastic exercise", generally "to train, to exercise". The verb had this meaning because one undressed for exercise. Historically, the gymnasium was used for exercise, communal bathing, and scholarly and philosophical pursuits. The English noun gymnast, first recorded in 1594, is formed from the Greek γυμναστής (gymnastēs), but in Greek this word means "trainer" not "athlete". The palaestra was the part of the gymnasium devoted to wrestling, boxing and ball games.
gymnasium, from the top of the stadium wall.