rotor

Noun

rotor (plural rotors)

1. A rotating part of a mechanical device; for example, in an electric motor, generator, alternator, or pump.
   • Turbines have been around for a long time—windmills and water wheels are early examples. The name comes from the Latin turbo, meaning vortex, and thus the defining property of a turbine is that a fluid or gas turns the blades of a rotor, which is attached to a shaft that can perform useful work.2013 July-August, Lee S. Langston, “The Adaptable Gas Turbine”, in American Scientist, archived from the original on 07 Sep 2013
   1. In a disc brake, the metal disc attached to the wheel hub.
   2. The wing of a helicopter or other rotary wing aircraft (e.g., heli-type drone).
2. A type of powerful horizontal-axis atmospheric vortex generated by the interaction of strong winds with mountainous terrain.
   • A glider instructor, who had been in the COS area for more than 25 years, was interviewed. He stated that around 1200 on the day of the accident, he observed a rotor hit the ground with estimated wind speeds of 70 to 80 miles per hour.2001, National Transportation Safety Board, “1.7.1 Observations and Forecasts”, in Uncontrolled Descent and Collision With Terrain, United Airlines Flight 585, Boeing 737-200, N999UA, 4 Miles South...
3. A quantity having magnitude, direction, and position.
   • These quantities are unit lengths measured anywhere on the axes in the positive directions. They have magnitude, direction, and position, and are thus what I have called rotors (short for rotators) to distinguish them from vectors, which have magnitude and direction but no position.1878, William Kingdon Clifford, “Applications of Grassmann's Extensive Algebra”, in American Journal of Mathematics, volume 1, number 4, →DOI, →ISSN, page 353
4. The set of cells within an oscillator that switch between being alive and dead over the course of the oscillator's period.
   • The following figure shows examples of the most versatile class of these oscillators. The first emulates the p10 shown above; the second has period 62 and a rotor of size 10.1997 November 30, David Bell, “Day & Night - An Interesting Variant of Life (part 2/5)”, in comp.theory.cell-automata (Usenet)
   • The problem of determining the asymptotic colouring for a cyclic pattern from a given initial black and white pattern is completely solved. The analysis leads to the proposal of the distinction between primary and secondary rotor cells (i.e. a refinement of the classical stator-rotor distinction).1998 March 18, Gunnar Johnsson, “Genetic aspects of the Game of Life.”, in comp.theory.cell-automata (Usenet)
5. An amusement park and carnival ride consisting of a rotating cylindrical chamber in which centrifugal force adheres riders to the wall as the floor drops away, creating a sensation of defying gravity.