General English

General Science

  • verb to repeat an operation or series of instructions until instructed to stop


  • noun a set of events which happen in a regularly repeated sequence


  • noun a series of actions which end at the same point as they begin


  • noun a period of time during which something leaves its original position and then returns to it

Cars & Driving

  • noun a sequence of changes of state after which the system is in its original state again



  • The flow of alternating current as it travels in one direction, then reverses itself and travels in the opposite direction. A 60-cycle circuit completes 60 cycles per second.


  • One complete sequence of changes of a periodically repeated phenomenon. For instance, an AC cycle.
  • One complete sequence of operations performed as a unit. For example, a machine cycle within a computer processor.
  • One complete sequence of events occurring as a unit, such as sunspot cycles.


  • verb to travel on a bicycle

Origin & History of “cycle”

Cycle is one of a wide range of English words (including pole, colony, and cult) which go back ultimately to the Indo-European base *qwel-, *qwol-, which signified ‘move around’. Its reduplicated form, *qweqwlo-, produced English wheel, Sanskrit cakrá- ‘wheel, circle’ (ultimate source of the polo term chukker (19th c.)), and Greek kúklos ‘circle’. English acquired this via French cycle or late Latin cyclus. Its use as a cover term for bicycles, tricycles, etc (of which words in this context it is an abbreviation) dates from the late 19th century. Related forms in English include cyclone ‘mass of rapidly circulating wind’ (19th c.) (probably a modification of Greek kúklōma), cyclamen (16th c.) (so named from its bulbous roots), and encyclopedia.