Track-and-field sport of hurling for distance a disk-shaped object known as a discus. The discus is 8.6 in. (219 mm) in diameter and is thicker in the centre than at the perimeter; it must weigh at least 4.4 lbs (2 kg) for men's events, 2.2 lbs (1 kg) for women's. It is thrown by means of a whirling movement made by the athlete within a circle 8.2 ft (2.5 m) in diameter. The sport dates back to the ancient Greek Olympics