A cycle Latin cyclus, from Greek κύκλος (pron. kyklos) meaning circle is anything round, in the physical sense (e.g. a bicycle) or in a temporal sense (e.g. the cycle of the seasons). Cyclic or cyclical are the adjective forms. Pages about cycles include:

Sports

• Cycling, the sport of riding a bicycle
• Hitting for the cycle in Baseball
• Paris-Roubaix Cycle Race.

Arts

• Cycle (music): Interval cycle, cyclic form and song cycle in music. Also in music, the cycle of fifths.
• Literature cycle, e.g. The Ring Cycle (more examples there).
• Sonnet cycle (examples there).
• The Cremaster Cycle, a sequence of five films by Matthew Barney.
• The Baroque Cycle, a series of books written by Neal Stephenson.
• The Pendragon Cycle, a series of books written by Stephen R. Lawhead.
• Northern Homily Cycle, a poem from the 14th century

History

• Indiction cycle was a cycle of 15 years used to date medieval documents
• Operation Cycle during World War II.
• Dynastic cycle in Chinese political theory.
• Sexagesimal cycle in Chinese philosophy and calendar
• Cyclical patterns in history.

Culture

• Cycles, a 1968 album by Frank Sinatra.
• A cycle path and (in Britain), the Sea to Sea Cycle Route and the National Cycle Network
• monomythic cycle of the hero.

Science

Astronomy

• Eclipse cycle and the Saros cycle.
• Solar cycle related to sunspots.
• solar cycle (calendar) related to days of the week in calendars.
• Full moon cycle.
• Metonic cycle in calendars.
• Sothic cycle in the ancient Egyptian calendar.
• Great year related to the precession of the equinoxes.

Biology

• life cycle
• Carbon cycle
• Cell cycle
• Citric acid cycle
• Earthworm organic cycle
• Eel life cycle
• Honeybee life cycle
• Human sexual response cycle
• Lytic cycle related to viruses
• Menstrual cycle
• Nitrogen cycle
• Nutrient cycle
• Phosphorus cycle
• Reproductive cycle
• Sleep cycle
• Urea cycle

Chemistry

• A series of chemical reactions. See e.g. Citric acid cycle, Kreb's cycle, the Born Haber cycle or the Calvin cycle.
• Biogeochemical cycles such as the Ozone-oxygen cycle (see list there).
• A cyclic compound. See also alicyclic compound

Physics

• The cycle is a unit of phase angle equivalent to one oscillation, or 2π radians. It appears in the once-common frequency unit cycle per second, which has now almost completely been supplanted by the Hertz.
• Consequently, in quantum optics, a Rabi cycle is that oscillation whose rate is the Rabi frequency.
• In astrophysics, the CNO cycle is a sequence of nuclear reactions whose net effect is fusion. It is the predominant fuel reaction in stars larger than the sun.

Geology

• Water cycle
• Rock cycle

Meteorology

• Milankovitch cycles in paleo-climatology
• Rapid Update Cycle for weather forecast

Engineering

• Otto cycle, the Diesel cycle, the two-stroke cycle, the Miller cycle and the Atkinson cycle in cars;
• Carnot cycle, Rankine cycle, Stirling cycle and Ericsson Cycle in heat engines;
• Brayton cycle in a gas turbine;
• combined cycle in power plants;
• Refrigeration cycle
  • Rocket liquid air cycle engine
  • expander cycle
  • Gas-generator cycle
  • Rocket Staged combustion cycle
  • Rocket Pressure-fed cycle
• The Nuclear fuel cycle
• Bicycle, tricycle and unicycle. See also Freight bicycle.
• Motorcycle.

Mathematics

• Cyclic permutation.
• Cyclic group.
• Cycle (graph theory) and a Hamiltonian cycle in graph theory. See also cycle space and Floyd's cycle-finding algorithm.
• A cycle is an element of a homology class. See also Hodge cycle.
• The Limit-cycle in dynamical systems, e.g. the Lotka-Volterra cycle.
• A cycle matroid.
• A cyclic order

Computer science

• Instruction cycle in a CPU
• "Computer cycles" are also a measure of the necessary time needed to be spent by a CPU to perform a certain task. Example: "I bet that banks use a lot of cycles to process their daily account transactions". See Instructions per second, FLOPS.

Military science

• Boyd cycle in military strategy.

Political science

• Top cycle, a notion in voting systems.

Business

Finance

• A cash conversion cycle.
• The related notions of product life cycle management, Life cycle cost analysis, life cycle assessment and systems development life cycle.
• Virtuous circle and vicious circle.
• A business cycle, e.g. the RBC.
• A cycle count is an inventory management procedure
• The Wright Cycle Company which funded the brothers' Wright aviation experiments.

Telecommunication

• Duty cycle in telecommunication.

Crime

• Cycle of violence, the cycle that can happen in Domestic abuse.

See also

• List of cycles
• Periodicity

Cyklus | Kreislauf | Cycle | Cyclus | サイクル | Cykl | Цикл | Цикл