Fire rocket is a term used to describe a type of rocket that is propelled by the combustion of fuel. It is a type of rocket that is used for a variety of purposes, such as launching satellites into space, providing propulsion for spacecraft, and providing thrust for missiles. The term 'fire rocket' is derived from the fact that the rocket is powered by the burning of fuel, which produces a large amount of heat and energy. The crossword solution for the term 'fire rocket' is 'LAUNCH, ' which is an appropriate description of the process of propelling a rocket using the combustion of fuel.