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 theo ...

, 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 betw ...

, a theory of American political history associated with Arthur Schlesinger, Sr. * Social cycle, various cycles in social sciences **

Business cycle Business cycles are intervals of expansion followed by recession in economic activity. These changes have implications for the welfare of the broad population as well as for private institutions. Typically business cycles are measured by examin ...

, 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 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 iden ...

, a set of musical pieces that belong together **

Cyclic form Cyclic form is a technique of musical construction, involving multiple sections or movements, in which a theme, melody, or thematic material occurs in more than one movement as a unifying device. Sometimes a theme may occur at the beginning and ...

, a technique of construction involving multiple sections or movements **

Interval cycle In music, an interval cycle is a collection of pitch classes created from a sequence of the same interval class.Whittall, Arnold. 2008. ''The Cambridge Introduction to Serialism'', p. 273-74. New York: Cambridge University Press. (pbk). In other w ...

, 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, of individually complete songs designed to be performed in a sequence as a unit.Susan Youens, ''Grove online'' The songs are either for solo voice or an ensemble, or rare ...

, 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 is a Japanese noise project started in 1979 by , best known for a style of harsh, confrontational noise. Since 1980, Akita has released over 400 recordings and has collaborated with various artists. The name Merzbow comes from the German dada ...

* ''Cycle'', a 2014 album by

Buckethead Brian Patrick Carroll (born May 13, 1969), known professionally as Buckethead, is an American guitarist, songwriter, and multi-instrumentalist. He has received critical acclaim for his innovative electric guitar playing. His music spans severa ...

* ''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

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-wa ...

, 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 A blender (sometimes called a mixer or liquidiser in British English) is a kitchen and laboratory appliance used to mix, crush, purée or emulsify food and other substances. A stationary blender consists of a blender container with a rotating me ...

Instruction cycle The instruction cycle (also known as the fetch–decode–execute cycle, or simply the fetch-execute cycle) is the cycle that the central processing unit (CPU) follows from boot-up until the computer has shut down in order to process instruction ...

, 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, refere ...

, 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 The cycle per second is a once-common English name for the unit of frequency now known as the hertz (Hz). The plural form was typically used, often written cycles per second, cycles/second, c.p.s., c/s, or, ambiguously, just cycles (Cy./Cyc.). The ...

, 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 one he ...

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 In graph theory, a cycle graph or circular graph is a graph that consists of a single cycle, or in other words, some number of vertices (at least 3, if the graph is simple) connected in a closed chain. The cycle graph with vertices is called ...

, a graph that is itself a cycle ** Cycle matroid, 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, the algorithmic problem of detecting eventual repetitions in sequences generated by iterated functions * Cycle, a set equipped with a

cyclic order In mathematics, a cyclic order is a way to arrange a set of objects in a circle. Unlike most structures in order theory, a cyclic order is not modeled as a binary relation, such as "". One does not say that east is "more clockwise" than west. In ...

Necklace (combinatorics) In combinatorics, a ''k''-ary necklace of length ''n'' is an equivalence class of ''n''-character strings over an alphabet of size ''k'', taking all rotations as equivalent. It represents a structure with ''n'' circularly connected beads which h ...

, equivalence classes of cyclically ordered sequences of symbols modulo certain symmetries * Cyclic (mathematics), a list of mathematics articles with "cyclic" in the title * Cyclic group, a group generated by a single element *

Cyclic permutation In mathematics, and in particular in group theory, a cyclic permutation (or cycle) is a permutation of the elements of some set ''X'' which maps the elements of some subset ''S'' of ''X'' to each other in a cyclic fashion, while fixing (that is, ...

, 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 ...

, 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 A cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where ...

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 Quadricycle refers to vehicles with four wheels. In 1896 Henry Ford named his first vehicle design the "Quadricycle". it ran on four bicycle wheels, with an engine driving the back wheels.Brinkley, David, ''Wheels for the World: Henry Ford, His ...

Tricycle A tricycle, sometimes abbreviated to trike, is a human-powered (or gasoline or electric motor powered or assisted, or gravity powered) three-wheeled vehicle. Some tricycles, such as cycle rickshaws (for passenger transport) and freight trikes ...

Unicycle A unicycle is a vehicle that touches the ground with only one wheel. The most common variation has a frame with a saddle, and has a pedal-driven direct-drive. A two speed hub is commercially available for faster unicycling. Unicycling is practice ...

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), a single, double, triple, and home run (in any order) by the same player in one game * Cycle, North Carolina, a community in the United States