how do rockets work and what is it?

what does the word rocket mean

The word "rocket" can mean different things. Most people think of a tall, thin, round vehicle. They think of a rocket that launches into space."Rocket" can mean a type of engine.The word also can mean a vehicle that uses that engine.
A rocket engine is different from a jet engine. A jet engine needs air to work. A rocket engine doesn't need air. It carries with it everything it needs. A rocket engine works in space, where there is no air.
How do rocket engines work - SpacePod