Rocket, Type of jet-propulsion device that uses either solid or liquid propellants to provide the fuel and oxidizer needed for combustion. The hot gases provided by combustion are ejected in a jet through a nozzle at the rear of the rocket. A rocket (from Italian: rocchetto, lit. ‘bobbin/spool’) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. A rocket is a manmade vehicle that uses thrust from a rocket engine to travel. Rockets are named after the Italian word “rocchetta”, which means “bobbin” or “little spindle”. Some of the first rockets, which were fireworks, have been traced back to the 13th century (1200s) in Medieval China during the Song dynasty. A rocket has four (4) main parts: nose cone, fins, rocket body, and engine. The nose cone carries the payload or cargo. Common payloads include astro- nauts, satellites, scientific instruments, and even explosives. Rockets deliver satellites to space where they can begin to do their important work. Without rockets, we wouldn’t be able to use our cell phones, watch a lot of our favorite television shows, find out the weather forecast, navigate with Global Positioning System (GPS), or explore our solar system—just to name a few. A rocket is a space vehicle that is shaped like a long tube. 2. countable noun [oft NOUN noun] A rocket is a missile containing explosive that is powered by gas. For the main frame most rockets use aerospace grade aluminum or titanium since both metals are very strong but light weight. Future rocket designs are even looking into using carbon composite structures. Aluminum, however, melts at the high reentry temperatures.