The Collaborative International Dictionary of English v.0.48:

ballistic missile \bal*lis"tic mis`sile\, n.
   A rocket-propelled missile of long range which is guided only
   during the powered portion of its flight, which usually takes
   only a small part of the total flight time; -- contrasted
   with guided missile.

   Note: Ballistic missiles are sometimes referred to by their
         range, such as an

   intercontinental ballistic missile (ICBM) or an

   intermediate range ballistic missile (IRBM).
      [PJC]