An ion thruster is a type of electric propulsion system that generates thrust by propelling ionized particles out of a nozzle. Synonyms for the term "ion thruster" include electric propulsion, electrostatic propulsion, ion engine, ion drive, plasma thruster, and electric rocket. These synonyms all refer to the same type of propulsion technology that utilizes an electric field to accelerate charged particles and create thrust. Ion thrusters are becoming increasingly popular for deep space exploration missions due to their efficiency and ability to operate for extended periods of time. As technology continues to advance, we may see further developments in ion thruster technology and new synonyms emerging to describe this complex propulsion system.