trebuchet

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A medieval catapult for hurling heavy stones.

Century Dictionary and Cyclopedia

1. n. In medieval warfare, a missile engine resembling the ballista. It was used especially by besiegers, for making a breach or for casting stones and other missiles into beleaguered towns and castles. It consisted of a beam called the verge, turning on a horizontal axis supported upon uprights. At one end of the verge was fixed a heavy weight, and at the other a sort of sling to contain the projectile—a device which greatly increased its force. To discharge the engine, the loaded end of the verge was drawn back by means of a windlass, and suddenly let go. It was possible to attain with the trebuchet great accuracy of fire. Prince Louis Napoleon, afterward Napoleon III., caused to be constructed in 1850 a model trebuchet which gave remarkable results.
2. n. A kind of balance or scales used in weighing coins or other small articles, the pan containing which tilts over if the balance is not exact.
3. n. A kind of trap for catching small birds or animals by the tilting of the part on which the bait is placed.
4. n. A cucking-stool.

Wiktionary

1. n. A medieval siege engine consisting of a large pivoting arm heavily weighted on one end. Considered to be the technological successor to the catapult.
2. n. A torture device for dunking suspected witches by means of a chair attached to the end of a long pole.

GNU Webster's 1913

1. n. A cucking stool; a tumbrel.
2. n. A military engine used in the Middle Ages for throwing stones, etc. It acted by means of a great weight fastened to the short arm of a lever, which, being let fall, raised the end of the long arm with great velocity, hurling stones with much force.
3. n. obsolete A kind of balance for weighing.

WordNet 3.0

1. n. an engine that provided medieval artillery used during sieges; a heavy war engine for hurling large stones and other missiles