The Collaborative International Dictionary of English v.0.48:

Missile \Mis"sile\, n. [L. missile.]
   1. A weapon thrown or projected or intended to be projected,
      as a lance, an arrow, or a bullet.
      [1913 Webster]

   2. A rocket-propelled device designed to fly through the air
      and deliver a warhead of explosive materials to a target.
      [PJC]

   Note: Numerous types of rocket-propelled missile[2] are now
         used in modern warfare. Some types with names
         indicating their range or function are: antiaircraft
         missile; ballistic missile; cruise missile;
         antiballistic missile missile; air-to-air missile;
         air-to-ground missile; guided missile;
         intercontinental ballistic missile (IBM);
         intermediate range ballistic missile (IRBM);
         surface-to-air missile.

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]

WordNet (r) 3.0 (2006):

ballistic missile
    n 1: a missile that is guided in the first part of its flight
         but falls freely as it approaches target