rotor

From an irregular clipping of rotator, originally in mathematics,^[1] coined by English mathematician and philosopher William Kingdon Clifford based on vector, see quotations. Doublet of rota and ruote.

• (UK) IPA^(key): /ˈɹəʊ.tə/

• Audio (Southern England):

  (file)

• (General American) IPA^(key): /ˈɹoʊ.tɚ/
• (US, non-rhotic) IPA^(key): /ˈɹoʊ.tə/

• Audio (US):

  (file)

• Rhymes: (UK) -əʊtə
• Homophones: rota, Rota (non-rhotic); Rhoda (non-rhotic, flapping)

rotor (plural rotors)

2. A rotating part of a mechanical device; for example, in an electric motor, generator, alternator, or pump. [from 1900s]
   • 2013 July-August, Lee S. Langston, “The Adaptable Gas Turbine”, in American Scientist‎^[1], archived from the original on 7 September 2013:

     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.

   2. (automotive, cycling) In a disc brake, the metal disc attached to the wheel hub.
   4. (aviation) The wing of a helicopter or other rotary wing aircraft (e.g., heli-type drone).

      Synonym: rotary wing

3. (meteorology) A type of powerful horizontal-axis atmospheric vortex generated by the interaction of strong winds with mountainous terrain.
   • 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 of Colorado Springs Municipal Airport, Colorado Springs, Colorado, March 3, 1991‎^[2], archived from the original on 22 January 2021, pages 30–31:

     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.

5. (mathematics, algebra) A quantity having magnitude, direction, and position.

   Coordinate term: vector

   • 1878, William Kingdon Clifford, “Applications of Grassmann's Extensive Algebra”, in American Journal of Mathematics, volume 1, number 4, →DOI, →ISSN, page 353:

     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.

6. (cellular automata) The set of cells within an oscillator that switch between being alive and dead over the course of the oscillator's period.
   • 1997 November 30, David Bell, “Day & Night - An Interesting Variant of Life (part 2/5)”, in comp.theory.cell-automata‎^[3] (Usenet):

     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.

   • 1998 March 18, Gunnar Johnsson, “Genetic aspects of the Game of Life.”, in comp.theory.cell-automata‎^[4] (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).

   • 2008 June 25, Dave Greene, “Life: B37/S23 - A Chaotic Universe.”, in comp.theory.cell-automata‎^[5] (Usenet):

     In B37/S23, it goes symmetrical after 10 ticks, and produces a familiar pair of B-heptominoes after 23 ticks (the next generation after this can be found in the rotor of a standard B3/S23 p46 oscillator):

7. 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.

• main rotor
• tail rotor
• wound rotor

• stator

• → Czech: rotor
• → French: rotor
• → German: Rotor
• → Polish: rotor
• → Portuguese: rotor
• → Spanish: rotor

• rotor (electric) on Wikipedia.Wikipedia
• helicopter rotor on Wikipedia.Wikipedia
• rotor (meteorology) on Wikipedia.Wikipedia
• rotor (mathematics) on Wikipedia.Wikipedia

Borrowed from English rotor, ultimately from Latin rota.

• IPA^(key): [ˈrotor]
• Rhymes: -otor

rotor m inan

1. rotor (rotating part of a mechanical device)

This noun needs an inflection-table template.

• “rotor”, in Příruční slovník jazyka českého (in Czech), 1935–1957
• “rotor”, in Slovník spisovného jazyka českého (in Czech), 1960–1971, 1989
• “rotor”, in Internetová jazyková příručka (in Czech), 2008–2026

Borrowed from Latin rotor.

• IPA^(key): /ˈroː.tɔr/, /ˈroː.tər/

• Audio:

  (file)

• Hyphenation: ro‧tor
• Rhymes: -oːtɔr, -oːtər

rotor m (plural rotoren or rotors, diminutive rotortje n)

1. rotor

• rotoras
• rotorblad

Borrowed from English rotor.

• IPA^(key): /ʁɔ.tɔʁ/

• Audio (France (Lyon)):

  (file)

rotor m (plural rotors)

1. rotor

• → Romanian: rotor

• “rotor”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012

Internationalism

• (Standard Indonesian) IPA^(key): /ˈrotor/ [ˈro.t̪ɔr]
• Rhymes: -otor
• Syllabification: ro‧tor

rotor (plural rotor-rotor)

1. rotor
   1. (electromagnetism, mechanical engineering) a rotating part of a mechanical device

• “rotor”, in Kamus Besar Bahasa Indonesia [Great Dictionary of the Indonesian Language] (in Indonesian), Jakarta: Agency for Language Development and Cultivation – Ministry of Education, Culture, Research, and Technology of the Republic of Indonesia, 2016

rotor

1. first-person singular present passive indicative of rotō

• "rotor", in Charles du Fresne du Cange, Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)

Borrowed from English rotor.

• IPA^(key): /ˈrɔ.tɔr/

• Audio:

  (file)

• Rhymes: -ɔtɔr
• Syllabification: ro‧tor

rotor m inan

1. rotor (rotating part of a mechanical device)

   Synonym: wirnik

2. rotor (propeller on a rotorcraft that provides lift)

   Synonym: wirnik

3. (meteorology) rotor (type of powerful horizontal-axis atmospheric vortex generated by the interaction of strong winds with mountainous terrain)

• “rotor”, in Polish dictionaries at PWN‎^[6] (in Polish)

Borrowed from English rotor.

• Hyphenation: ro‧tor

rotor m (plural rotores)

1. rotor (a rotating part of a mechanical device)
2. rotor (central part of a helicopter’s wings)

• “rotor”, in Dicionário Aulete Digital (in Portuguese), Rio de Janeiro: Lexikon Editora Digital, 2008–2026
• “rotor”, in Dicionário Infopédia da Língua Portuguesa (in Portuguese), Porto: Porto Editora, 2003–2026
• “rotor”, in Dicionário Priberam da Língua Portuguesa (in Portuguese), Lisbon: Priberam, 2008–2026

Borrowed from French rotor, from English rotor.

rotor n (plural rotoare)

1. rotor

• IPA^(key): /rôːtor/
• Hyphenation: ro‧tor

rȏtor m inan (Cyrillic spelling ро̑тор)

1. rotor

Borrowed from English rotor.

• IPA^(key): /roˈtoɾ/ [roˈt̪oɾ]
• Rhymes: -oɾ
• Syllabification: ro‧tor

rotor m (plural rotores)

1. rotor

• “rotor”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8.1, Royal Spanish Academy [Spanish: Real Academia Española], 15 December 2025

rotor (definite accusative rotoru, plural rotorlar)

1. (aviation) rotor