Meaning

noun a large structure for open-air sports or entertainments

originFrom Latin stadium (“a measure of length, a race course”) (commonly one-eighth of a Roman mile; translated in early English Bibles by furlong), from Ancient Greek στάδιον (stádion, “a measure of length, a running track”), especially the track at Olympia, which was one stadium in length. The Greek word may literally mean "fixed standard of length" (from στάδιος (stádios, “firm, fixed”), from…

Etymology from Wiktionary, CC BY-SA 3.0