boomerang

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A flat, curved, usually wooden missile configured so that when hurled it returns to the thrower.
2. n. A statement or course of action that backfires.
3. v. To have the opposite effect from the one intended; backfire.

Century Dictionary and Cyclopedia

1. n. A missile weapon of war and the chase, used by the aborigines of Australia, consisting of a rather flat piece of hard wood bent or curved in its own plane, and from 16 inches to 2 feet long. Generally, but not always, it is flatter on one side than on the other. In some cases the curve from end to end is nearly an arc of a circle, in others it is rather an obtuse angle than a curve, and in a few examples there is a slight reverse curve toward each end. In the hands of a skilful thrower the boomerang can be projected to great distances, and can be made to ricochet almost at will; it can be thrown in a curved path, somewhat as a bowl can be “screwed” or “twisted,” and it can be made to return to the thrower, and strike the ground behind him. It is capable of inflicting serious wounds.
2. n. Hence Figuratively, any plan, measure, or project the consequences of which recoil upon the projector, and are therefore the opposite of those intended or expected.

Wiktionary

1. n. A flat curved airfoil, that spins about an axis perpendicular to the direction of flight, that was originally used in various parts of the world as hunting weapons or, in returnable types, for sports or training.
2. v. To return to the starting point.
3. v. To travel in a curved path.
4. v. To return or rebound unexpectedly, especially when the result is undesired; to backfire.

GNU Webster's 1913

1. n. A very singular missile weapon used by the natives of Australia and in some parts of India. It is usually a curved stick of hard wood, from twenty to thirty inches in length, from two to three inches wide, and half or three quarters of an inch thick. When thrown from the hand with a quick rotary motion, it describes very remarkable curves, according to the shape of the instrument and the manner of throwing it, often moving nearly horizontally a long distance, then curving upward to a considerable height, and finally taking a retrograde direction, so as to fall near the place from which it was thrown, or even far in the rear of it.

WordNet 3.0

1. v. return to the initial position from where it came; like a boomerang
2. n. a miscalculation that recoils on its maker
3. n. a curved piece of wood; when properly thrown will return to thrower