A trebuchet is a kind of catapult that was used to hurl heavy stones or other projectiles during battles in the Middle Ages. Don't try using a trebuchet for a spit wad. A straw will suffice.
Trebuchets were the most powerful catapults used in the Middle Ages, and they were important weapons during military siege attacks on enemy fortifications. Using a counterweight, a trebuchet could hurl an extremely large and heavy rock very fast, potentially causing a lot of damage. The twelfth century Old French word trebuchet means "siege engine," from trabucher, "to overturn or overthrow."