rotor

A rotor is a component that revolves within a stationary part. In electrical machines, it's the rotating member. In rotorcraft, it's an assembly of rotating blades that provide lift or stability.1

Rotary engines, like the Wankel engine, differ from conventional piston engines. Instead of pistons moving in cylinders, they use a rotor. In a Wankel engine, an equilateral triangular rotor orbits within a specially shaped casing, creating combustion chambers. The pressure from combustion rotates the shaft.23

Turbines also feature a rotor. In a steam turbine, the rotor carries blades that convert steam's thermal energy into rotational motion. This design allows for significant power generation in a compact space.4