boomerang

Universal Words noun, verb noun a curved flat piece of wood that you throw and that can fly in a circle and come back to you. Boomerangs were first used by Australian ABORIGINES as weapons when they were hunting: (figurative) The plan had a boomerang effect (= caused unexpected harm to the person responsible for it). verb [V] if a plan boomerangs on sb, it hurts them instead of the person it was intended to hurt SYNBACKFIRE