#rocket_engine__rocket  a jet engine containing its own propellant and driven by reaction propulsion
  supertype:  jet_engine__jetengine  a gas turbine produces a stream of hot gas that propels a jet plane by reaction propulsion
  subtype:  takeoff_booster  nuclear_rocket  retrorocket  space_rocket  thruster
  part of:  rocket  any vehicle propelled by a rocket engine

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