A boomerang is a thrown tool, typically constructed as a flat airfoil, that is designed to spin about an axis perpendicular to the direction of its flight. A returning boomerang is designed to return to the thrower. It is well known as a weapon used by Indigenous Australians for hunting. Returning boomerangs were also used to decoy birds of prey, thrown above the long grass to frighten game birds into flight and into waiting nets.

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