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]