Webster’s Revised Unabridged Dictionary · 1913
Trebuchet
Treb′u·chet, Tre′buck·et, n. [OF. trebuchet, trebukiet, an engine of war for hurling stones, F. trébuchet a gin, trap, a kind of balance, fr. OF. trebuchier, trebuquier, to stumble, trip, F. trébucher.] 1. A cucking stool; a tumbrel. Cowell.
2. 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. A kind of balance for weighing. [Obs.]