Cycle, cycles, or cyclic may refer to:

Anthropology and social sciences

Cyclic history Social cycle theories are among the earliest social theories in sociology. Unlike the theory of social evolutionism, which views the evolution of society and human history as progressing in some new, unique direction(s), sociological cycle theory ...

, a theory of history *

Cyclical theory The cyclical theory refers to a model used by historians Arthur M. Schlesinger Sr. and Arthur M. Schlesinger Jr. to explain the fluctuations in politics throughout American history. In this theory, the United States's national mood alternates betwe ...

, a theory of American political history associated with Arthur Schlesinger, Sr. *

Social cycle Social cycle theories are among the earliest social theories in sociology. Unlike the theory of social evolutionism, which views the evolution of society and human history as progressing in some new, unique direction(s), sociological cycle theory ...

, various cycles in social sciences ** Business cycle, the downward and upward movement of gross domestic product (GDP) around its ostensible, long-term growth trend

Arts, entertainment, and media

Films

* ''Cycle'' (2008 film), a Malayalam film * ''Cycle'' (2017 film), a Marathi film

Literature

* ''Cycle'' (magazine), an American motorcycling enthusiast magazine *

Literary cycle A literary cycle is a group of stories focused on common figures, often (though not necessarily) based on mythical figures or loosely on historical ones. Cycles which deal with an entire country are sometimes referred to as matters. A fictional c ...

, a group of stories focused on common figures

Music

Musical terminology

Cycle (music) Cycle has several meanings in the field of music. Acoustically, it refers to one complete vibration, the base unit of Hertz being one cycle per second. Theoretically, an interval cycle is a collection of pitch classes created by a sequence of ident ...

, a set of musical pieces that belong together ** Cyclic form, a technique of construction involving multiple sections or movements ** Interval cycle, a collection of pitch classes generated from a sequence of the same interval class **

Song cycle A song cycle (german: Liederkreis or Liederzyklus) is a group, or cycle (music), cycle, of individually complete Art song, songs designed to be performed in a sequence as a unit.Susan Youens, ''Grove online'' The songs are either for solo voice ...

, individually complete songs designed to be performed in a sequence as a unit

Albums

* ''Cycle'' (album), a 1965 album by the Paul Horn Quintet * ''Cycle'', a 2003 album by Merzbow * ''Cycle'', a 2014 album by Buckethead * ''Cycles'' (Cartel album), 2009 * ''Cycles'' (David Darling album), 1981 * ''Cycles'' (The Doobie Brothers album), 1989 * ''Cycles'' (Frank Sinatra album), 1968 * ''Cycles'' (Redbone album), 1977 * ''Cycles'', a 2021 album by

Sam Teskey Sam Teskey (born 1989) is an Australian blues musician, best known for his work with the Teskey Brothers. Sam won the ARIA Award for Engineer of the Year in 2019. His debut studio album, ''Cycles'', was released on 8 October 2021 via Ivy Leag ...

Songs

* "Cycles" (song), a 2018 song by Tove Lo * "Cycle" an interlude by Beck from ''

Morning Phase ''Morning Phase'' is the twelfth official studio album and twelfth overall by American singer Beck. The album was released in February 2014 by his new label, Capitol Records. According to a press release, ''Morning Phase'' is a "companion piece" ...

'', 2014

Science, technology, and mathematics

Biology

Cycle (gene) ''Cycle'' (''cyc'') is a gene in ''Drosophila melanogaster'' that encodes the CYCLE protein (CYC). The ''Cycle'' gene ''(''c''yc)'' is expressed in a variety of cell types in a circadian manner. It is involved in controlling both the sleep-wak ...

, a gene in Drosophila melanogaster that encodes the CYCLE protein *

Cyclic flower A cyclic flower is a flower type formed out of a series of whorls; sets of identical organs attached around the axis at the same point. Most flowers consist of a single whorl of sepals termed a calyx; a single whorl of petals termed a corolla; one ...

, in botany, one way in which flower parts may be arranged *

Menstrual cycle The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that make pregnancy possible. The ovarian cycle controls the production and release of eggs a ...

Computing

* Cycles, a render engine for the software Blender * Instruction cycle, the time period during which a computer processes a machine language instruction *

Reference cycle In computer science, reference counting is a programming technique of storing the number of references, pointers, or handles to a resource, such as an object, a block of memory, disk space, and others. In garbage collection algorithms, referen ...

, where a software object refers directly or indirectly to itself

Mathematics

Cycle (algebraic topology) In algebraic topology, a -chain is a formal linear combination of the -cells in a cell complex. In simplicial complexes (respectively, cubical complexes), -chains are combinations of -simplices (respectively, -cubes), but not necessarily connecte ...

, a simplicial chain with 0 boundary * Cycle per second, a unit of frequency, the modern equivalent being

hertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that on ...

Cycle (graph theory) In graph theory, a cycle in a graph is a non-empty trail in which only the first and last vertices are equal. A directed cycle in a directed graph is a non-empty directed trail in which only the first and last vertices are equal. A graph witho ...

, a nontrivial path in a graph from a node to itself ** Cycle graph, a graph that is itself a cycle **

Cycle matroid In the mathematical theory of matroids, a graphic matroid (also called a cycle matroid or polygon matroid) is a matroid whose independent sets are the forests in a given finite undirected graph. The dual matroids of graphic matroids are called co- ...

, a matroid derived from the cycle structure of a graph *

Cycle (sequence) In mathematics, a periodic sequence (sometimes called a cycle) is a sequence for which the same terms are repeated over and over: :''a''1, ''a''2, ..., ''a'p'', ''a''1, ''a''2, ..., ''a'p'', ''a''1, ''a''2, ..., ''a'' ...

, a sequence with repeating values **

Cycle detection In computer science, cycle detection or cycle finding is the algorithmic problem of finding a cycle in a sequence of iterated function values. For any function that maps a finite set to itself, and any initial value in , the sequence of itera ...

, the algorithmic problem of detecting eventual repetitions in sequences generated by iterated functions * Cycle, a set equipped with a cyclic order ** Necklace (combinatorics), equivalence classes of cyclically ordered sequences of symbols modulo certain symmetries *

Cyclic (mathematics) There are many terms in mathematics that begin with cyclic: * Cyclic chain rule, for derivatives, used in thermodynamics * Cyclic code, linear codes closed under cyclic permutations * Cyclic convolution, a method of combining periodic functions * C ...

, a list of mathematics articles with "cyclic" in the title * Cyclic group, a group generated by a single element * Cyclic permutation, a basic permutation (all permutations are products of cycles)

Other uses in science and technology

Charge cycle A charge cycle is the process of charging a rechargeable battery and discharging it as required into a load. The term is typically used to specify a battery's expected life, as the number of charge cycles affects life more than the mere passage of t ...

, charging and discharging a rechargeable battery *

Thermodynamic cycle A thermodynamic cycle consists of a linked sequence of thermodynamic processes that involve transfer of heat and work into and out of the system, while varying pressure, temperature, and other state variables within the system, and that eventuall ...

, a sequence of processes that involve transfer of heat and work into and out of a system * Cyclic, a primary flight control for helicopters * Cyclic compound

Vehicles

Bicycle A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bic ...

Motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

* Quadricycle * Tricycle *

Unicycle A unicycle is a vehicle that touches the ground with only one wheel. The most common variation has a bicycle frame, frame with a bicycle saddle, saddle, and has a human-powered vehicle, pedal-driven direct-drive mechanism, direct-drive. A two spee ...

Other uses

Cycling Cycling, also, when on a two-wheeled bicycle, called bicycling or biking, is the use of cycles for transport, recreation, exercise or sport. People engaged in cycling are referred to as "cyclists", "bicyclists", or "bikers". Apart from two ...

, a sport *

Cycle (baseball) In baseball, hitting for the cycle is the accomplishment of one batter who hits a single, a double, a triple, and a home run in the same game. Collecting the hits in that order is known as a "natural cycle". Cycles are rare in Major League Bas ...

, a single, double, triple, and home run (in any order) by the same player in one game *

Cycle, North Carolina Cycle is an unincorporated community in Yadkin County, North Carolina, United States. History A post office A post office is a public facility and a retailer that provides mail services, such as accepting letters and parcels, providing po ...

, a community in the United States