File:Aztec atl-atl (Museo Nacional de Antropología).jpg

English: An atlatl or spear-thrower is a tool that uses leverage to achieve greater velocity in dart-throwing, and includes a bearing surface which allows the user to temporarily store energy during the throw.

It consists of a shaft with a cup or a spur, which may be integrated into the weapon or made separately and attached, in which the butt of the projectile, properly called a dart, rests. The atlatl is held in one hand, gripped near the end farthest from the cup. The dart is thrown by the action of the upper arm and wrist in combination with the atlatl as an extension of the throwing arm, adding significant force through increased angular momentum. Common dog ball-throwers (molded plastic shafts used for throwing tennis balls for dogs to fetch) use the same principles and in effect are a type of atlatl.

A traditional atlatl is a long-range weapon and can readily achieve speeds of over 150 km/h (93 mph).