boomerang
boom•er•ang (bōm´əraŋ´) n.
[[< name in a language of Australia]]
1 a flat, curved stick that can be thrown so that it will return to a point near the thrower: it is used as a weapon by Australian Aborigines
2 something that goes contrary to expectations and results in disadvantage or harm to the person doing or saying it
—vi. to act as a boomerang; result in harm to the originator
