In antiquity, a round or oval edifice, used for the exhibition of games and shows to the people. The Roman circus was encompassed with porticos, and furnished with rows of seats, rising one above another for the accommodation of spectators. The Circus Maximus was nearly a mile in circumference.

The open area, or space inclosed, in which were exhibited games and shows; as wrestling, fighting with swords, staves or pikes, running or racing, dancing, quoits.

In modern times, a circular inclosure for the exhibition of feats of horsemanship.