Noun
(astronautics) A rocket engine (rocket motor) that uses a solid propellant that, when combusted, generates gases which are used for rocket propulsion.
(astronautics) A rocket that uses such an engine.
Source: en.wiktionary.orgThere was a lot of light and a lot of rumbling and vibration, especially the first minute or minute-and-a-half. And then after about two minutes, when the solid rocket boosters separated, the ride got a lot smoother. Ellen Ochoa