A period of four years reckoned from one celebration of the Olympic games to another, and constituting an important epoch in history and chronology. The first olympiad commenced 775 years before the birth of Christ, and 22 years before the foundation of Rome. The computation by Olympiads ceased at the three hundred and sixty fourth olympiad in the year 440 of the christian era.

A period of four years, by which the ancient Greeks reckoned time, being the interval from one celebration of the Olympic games to another, beginning with the victory of Cor/bus in the foot race, which took place in the year 776 b.c.; as, the era of the olympiads.