[1] : The Collaborative International Dictionary of English v.0.48

ballista \ballis"ta\, n.; pl. ballistae. l. ballista,
   balista, fr. gr. ba`llein to throw.
   an ancient military engine, in the form of a crossbow, used
   for hurling large missiles.
   1913 webster
see also:
ballistae 

[2] : WordNet (r) 2.0

ballista
     n : medieval artillery used during sieges; a heavy war engine
         for hurling large stones and other missiles syn: catapult,
          arbalest, arbalist, bricole, mangonel, onager,
          trebuchet, trebucket
     also: ballistae pl
see also:
catapult arbalest arbalist bricole mangonel onager 
trebuchet trebucket ballistae 

Ballista >> B Words
Ballista, definition of term: Ballista
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