noun: (computing) Initialism of Revision Control System.
noun: (electronics, aviation) Initialism of radar cross section.
noun: (US, space science, aviation) Initialism of Reaction Control System: NASA designation for attitude thrusters that provide attitudinal control for a spacecraft.
noun: Initialism of Royal College of Surgeons of England.
noun: (UK, military) Initialism of Royal Corps of Signals.