The term 'Loud Engine Sound' can be summarized as 'ROAR', which is a four letter word. Roaring is a sound that is often associated with engines, such as those found in cars and airplanes. It is a loud, deep sound that is created by the engine's combustion process. The sound is usually caused by the rapid expansion of air and fuel in the engine's cylinders. This sound is often used to indicate power and strength.