Definition of cycle in English:

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Pronunciation: /ˈsīk(ə)l/


1 [often with adjective or noun modifier] A series of events that are regularly repeated in the same order: the boom and slump periods of a trade cycle
More example sentences
  • Any civilisation requires regular repeating cycles in order to be able to function properly.
  • The reality, as we have seen, is that eclipses are not random at all; they repeat on regular cycles.
  • Each discrete section of animation is brief and each repeats in a regular cycle.
round, rotation;
pattern, rhythm
1.1The period of time taken to complete a single sequence of events: the cells are shed over a cycle of twenty-eight days
More example sentences
  • Dr Perrett said that hepatitis A has a natural periodic cycle of about seven years, which would explain two outbreaks in such quick succession.
1.2 technical A recurring series of successive operations or states, as in the working of an internal combustion engine, or in the alternation of an electric current or a wave: the familiar four cycles of intake, combustion, ignition, and exhaust
More example sentences
  • At the sub-femtosecond level, a laser pulse contains only a few cycles of the carrier electromagnetic wave.
  • The quantum and classical Carnot engines therefore operate in the same way - a closed cycle of two isothermal and two adiabatic processes.
  • Hydrogen must replace fossil fuels through efficient production using solar radiation, thermochemical cycles, or bioinspired catalysts to split water.
1.3 Biology A recurring series of events or metabolic processes in the lifetime of a plant or animal: the storks' breeding cycle
More example sentences
  • Two things I've been interested in recently are the brain's visual processing, and the metabolic cycle.
  • As a consequence, most biological processes, from sleep-wake cycles in people to leaf movements in plants, follow a daily, circadian rhythm.
  • These metabolic cycles allow large and rapid changes in the net rate of sucrose breakdown in response to the demand in the cell, even though the steady-state concentrations of metabolites hardly change.
1.4 Biochemistry A series of successive metabolic reactions in which one of the products is regenerated and reused.
Example sentences
  • PCR was carried out in limited cycles in which PCR products exponentially increased and reflected the initial quantity of RNA.
1.5 Ecology The movement of a simple substance through the soil, rocks, water, atmosphere, and living organisms of the earth. See carbon cycle, nitrogen cycle.
Example sentences
  • Looking at the needs of diverse forests and soils, and the cycles of water and air, the evidence suggests that North America, the planet also, is already overpopulated by humans.
  • Deforestation also can have regional climatic effects because trees are a key link in the evapotranspiration cycle between soil and the atmosphere.
  • Once cooled to body temperature, the water then completes its cycle by being returned to the ground where it slowly irrigates a grove of mesquite trees that form a new desert park.
1.6 Computing A single set of hardware operations, especially that by which memory is accessed and an item is transferred to or from it, to the point at which the memory may be accessed again.
Example sentences
  • Grid software makes collections of computers more efficient by allowing them to share CPU cycles, memory and other resources so closely that they act almost like a single computer.
  • The resources that are important from an active networking point of view include CPU cycles, main memory, and outgoing network bandwidth.
  • These are typically scientific or technical and require a great number of computer processing cycles or access to large amounts of data.
1.7 Physics A cycle per second; one hertz.
Example sentences
  • Different frequencies, measured in hertz, or cycles per second, indicate different levels and types of activities.
  • The rate at which an object vibrates is measured in Hertz or cycles per second.
  • Optical clocks, with frequencies measured near 10 cycles per second, promise greater accuracy.
2A complete set or series: the painting is one of a cycle of seven
More example sentences
  • The planned cycle of seven books is underpinned by the conceit that there should be one book for each day of the week.
  • The play is part of Wilson's decade-by-decade cycle examining African-American life in the 20th century.
  • About a dozen stories will be performed from the full cycle of 50 plays, retelling the Bible's account of mankind from God's Creation to Judgment Day.
series, sequence, succession, run;
2.1A series of songs, stories, plays, or poems composed around a particular theme and usually intended to be performed or read in sequence: Wagner’s Ring Cycle
More example sentences
  • Few established contemporary poets have shown the commitment or innovation displayed by Wearne in writing the long cycles of thematic poems.
  • Reading the text as a short story cycle and not just a collection reveals Lahiri's careful balancing of a range of representations and her intricate use of pattern and motif.
  • Akhmatova wrote a poem cycle called Cinque which was based on their evenings together.
3A bicycle or tricycle.
Example sentences
  • Race officials today announced they will be awarding two mountain cycles to volunteers aiding the effort in this year's race.
  • The sheer number of people in attendance has reduced the road to barely the width of two cycles.
  • Sidharth rides a cycle selling tea and coffee in bus and railway stations to make a living.
3.1 [in singular] A ride on a bicycle: a 112-mile cycle
More example sentences
  • Today it is a blazing day in the capital, Maputo, and I have stayed on alone here for a few days, while the team continues the cycle northwards.
  • Michael and Bernard provided one of the attractions on the day when they completed the cycle on a tandem bike.


[no object]
1Ride a bicycle: she cycled to work every day
More example sentences
  • Jimmy Bergin from Abbeyleix took out his bicycle and cycled 28 miles to raise funds.
  • You could cycle, ride or kayak, but, personally, I prefer to trust my own two legs.
  • I opted to cycle for an hour out of London and then turn round, whatever the distance covered.
ride (a bicycle), bike, pedal
2Move in or follow a regularly repeated sequence of events: economies cycle regularly between boom and slump
More example sentences
  • The frame includes a predefined number of time slots that are cycled through in sequence.
  • Do one or two speed workouts a week, cycling through three different programs.
  • Ideally, each lesson would cycle repeatedly through the romance, precision and generalization stages.


Late Middle English: from Old French, from late Latin cyclus, from Greek kuklos 'circle'.

  • wheel from Old English:

    The wheel was probably invented some time around 4000 bc in Mesopotamia (present-day Iraq). Its name, probably based on a word meaning ‘to turn’, moved east to India, where it produced Sanskrit cakra ‘wheel, circle’, source of the chakra (late 19th century) of yoga, and west, where it gave rise to Greek kuklos ‘circle’, the source of cycle (Late Middle English) and cyclone (mid 19th century). It is recorded in Anglo-Saxon English from about ad 900. To reinvent the wheel is a 20th-century expression. Wheels within wheels is an allusion to a biblical quotation from the Old Testament book of Ezekiel. The prophet Ezekiel sees a vision in which four cherubs appear: ‘And as for their appearances, they four had one likeness, as if a wheel had been in the midst of a wheel’.

Words that rhyme with cycle

Carmichael, cervical, Michael

For editors and proofreaders

Syllabification: cy·cle

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