Supersonic aircraft is a term that is commonly used to describe planes capable of reaching speeds faster than the speed of sound. Although this term is widely used, there are several synonyms that can be used to describe supersonic aircraft. For example, the term "hypersonic aircraft" can be used to describe planes that are capable of travelling at incredibly high speeds, reaching Mach 5 or greater. Another synonym for supersonic aircraft is "sonic boom aircraft". This term is used to describe planes that create a loud sound when they break the sound barrier. Additionally, the term "supercruise aircraft" can be used to describe planes that can maintain supersonic speeds without using an afterburner.