From The Collaborative International Dictionary of English v.0.48 [gcide]:
Boomerang \Boom"er*ang\, noun 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.
From WordNet (r) 3.0 (2006) [wn]:
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