The javelin throw is a track and field event where the javelin, a spear is thrown. The javelin thrower gains momentum by running within a predetermined area. Javelin throwing is an event of both the men's decathlon and the women's heptathlon.

The size, shape, minimum weight, and center of gravity of the javelin are all defined by IAAF rules. In international competition, men throw a javelin between 2.6 and 2.7 m (8 ft 6 in and 8 ft 10 in) in length and 800 g (28 oz) in weight, and women throw a javelin between 2.2 and 2.3 m (7 ft 3 in and 7 ft 7 in) in length and 600 g (21 oz) in weight.

The javelin has a grip, about 150 mm (5.9 in) wide, made of cord and located at the javelin's center of gravity (0.9 to 1.06 m (2 ft 11 in to 3 ft 6 in) from the javelin tip for the men's javelin and 0.8 to 0.92 m (2 ft 7 in to 3 ft 0 in) from the javelin tip for the women's javelin).

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