Ramjet is a type of jet engine that operates at a high speed and is used mainly in supersonic flight. There are various synonyms for the word ramjet, including supersonic combustion ramjet, air-breathing jet engines, scramjet, and pulsejet. A supersonic combustion ramjet is an engine that uses the air intake to compress and ignite fuel in a continuous combustion process. Another synonym is the air-breathing jet engine, which describes engines that use the surrounding air for combustion and propulsion. A scramjet is a supersonic combustion ramjet designed to operate at extremely high speeds, while a pulsejet uses a series of explosions for propulsion. These synonyms help to define and differentiate the different types of jet engines used in aviation.