What does rotor mean?
A rotor is a component that rotates, especially the large assembly of blades that provides lift in a helicopter. The word also applies to the rotating elements of electric motors, turbines, generators, and wind turbines. In aviation, rotor may refer either to the complete helicopter rotor system or, depending on context, to its central hub and blades. As a general mechanical term, it emphasizes the rotating part of a device and often contrasts with a stationary component such as a stator. The word is especially useful in discussions of aviation, engineering, wind power, and machinery because it identifies the moving assembly that produces or transmits rotational force.
nounA rotating component of a machine, especially the large spinning assembly of a helicopter or other aircraft. More broadly, it refers to any rotating part, such as the wheel of an electric motor or the rotor of a wind turbine.
- A rotating component, especially the main lifting assembly of a helicopter.
- Any rotating part of a motor, turbine, generator, or similar machine.
- The rotating assembly of a wind turbine.
"The helicopter's rotor slowed as the aircraft prepared to land."
"Engineers inspected the rotor for signs of damage after the flight."
"The wind turbine's rotor was turning slowly in the morning breeze."
The plural is formed by adding -s. In aviation, rotors may refer to separate rotating assemblies, such as the main and tail rotors of a helicopter.
"The aircraft uses two rotors to maintain stability."
A helicopter's rotor can turn millions of times in a single flight, yet its spinning blades are designed to move as one controlled system.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does rotor come from?
The word entered English in the late 19th century from German Rotor, a term used for a rotating wheel or assembly. German had borrowed the word from Latin rotor, meaning “a wheel,” which developed from the same Latin root as rota, “wheel.” The Latin verb rotare, “to turn,” and its relatives rotation and rotary share this origin.
Related word forms
How rotor is actually used
In aviation, the term most often refers specifically to a helicopter's main rotor assembly. In engineering, it is a general technical term for a rotating component, often distinguished from the stationary part called the stator.