Source : Webster's Revised Unabridged Dictionary (1913)

Catapult \Cat"a*pult\, n. [L. catapulta, Gr. ?, prob. from kata`
   down + ? to shake, hurl.]
   1. (Mil. Antiq.) An engine somewhat resembling a massive
      crossbow, used by the ancient Greeks and Romans for
      throwing stones, arrows, spears, etc.

   2. A forked stick with elastic band for throwing small
      stones, etc.

Source : WordNet®

catapult
     n 1: a plaything consisting of a Y-shaped stick with elastic
          between the arms; used to propel small stones [syn: {slingshot},
           {sling}]
     2: a device that launches aircraft from a warship [syn: {launcher}]
     3: medieval artillery used during sieges; a heavy war engine
        for hurling large stones and other missiles [syn: {arbalest},
         {arbalist}, {ballista}, {bricole}, {mangonel}, {onager},
        {trebuchet}, {trebucket}]
     v 1: shoot forth or launch, as if from a catapult; "the enemy
          catapulted rocks towards the fort"
     2: hurl as if with a sling [syn: {sling}]