Radical may refer to:

Politics and ideology

Politics

Radical politics Radical politics denotes the intent to transform or replace the principles of a society or political system, often through social change, structural change, revolution or radical reform. The process of adopting radical views is termed rad ...

, the political intent of fundamental societal change * Radicalism (historical), the Radical Movement that began in late 18th century Britain and spread to continental Europe and Latin America in the 19th century *

Radical Party (disambiguation) Radical Party may refer to any of a number of political parties professing the progressive-liberal ideology known as Radicalism: Worldwide * Nonviolent Radical Party Transnational and Transparty (1989–present) Europe In the western Mediter ...

, several political parties *

Radicals (UK) The Radicals were a loose parliamentary political grouping in Great Britain and Ireland in the early to mid-19th century who drew on earlier ideas of radicalism and helped to transform the Whigs into the Liberal Party. History Early Radi ...

, a British and Irish grouping in the early to mid-19th century *

Radicalization Radicalization (or radicalisation) is the process by which an individual or a group comes to adopt increasingly views in opposition to a political, social, or religious status quo. The ideas of society at large shape the outcomes of radicalizat ...

Ideologies

* Radical chic, a term coined by Tom Wolfe to describe the pretentious adoption of radical causes *

Radical feminism Radical feminism is a perspective within feminism that calls for a radical re-ordering of society in which male supremacy is eliminated in all social and economic contexts, while recognizing that women's experiences are also affected by other ...

, a perspective within feminism that focuses on patriarchy *

Radical Islam Islamic extremism, Islamist extremism, or radical Islam, is used in reference to extremist beliefs and behaviors which are associated with the Islamic religion. These are controversial terms with varying definitions, ranging from academic unde ...

, or Islamic extremism * Radical veganism, a radical interpretation of veganism, usually combined with anarchism *

Radical Reformation The Radical Reformation represented a response to corruption both in the Catholic Church and in the expanding Magisterial Protestant movement led by Martin Luther and many others. Beginning in Germany and Switzerland in the 16th century, the Rad ...

, an Anabaptist movement concurrent with the Protestant Reformation

Science and mathematics

Science

Radical (chemistry) In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired electron, unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemical reaction, chemi ...

, an atom, molecule, or ion with unpaired valence electron(s) *

Radical surgery Radical surgery, also called radical dissection, is surgery that is more extensive than "conservative" surgery. In surgical oncology, radical surgery is surgery intended to remove both a tumor and any metastases thereof, for diagnostic and/or tre ...

, where diseased tissue or lymph nodes are removed from a diseased organ

Mathematics

Radical expression In mathematics, a radicand, also known as an nth root, of a number ''x'' is a number ''r'' which, when raised to the power ''n'', yields ''x'': :r^n = x, where ''n'' is a positive integer, sometimes called the ''degree'' of the root. A root ...

involving roots, also known as an ''n''th root *

Radical symbol In mathematics, the radical sign, radical symbol, root symbol, radix, or surd is a symbol for the square root or higher-order root of a number. The square root of a number x is written as :\sqrt, while the nth root of x is written as :\sqrt I ...

(√), used to indicate the square root and other roots * Radical of an algebraic group, a concept in algebraic group theory *

Radical of an ideal In ring theory, a branch of mathematics, the radical of an ideal I of a commutative ring is another ideal defined by the property that an element x is in the radical if and only if some power of x is in I. Taking the radical of an ideal is calle ...

, an important concept in abstract algebra *

Radical of a ring In ring theory, a branch of mathematics, a radical of a ring is an ideal of "not-good" elements of the ring. The first example of a radical was the nilradical introduced by , based on a suggestion of . In the next few years several other radic ...

, an ideal of "bad" elements of a ring **

Jacobson radical In mathematics, more specifically ring theory, the Jacobson radical of a ring R is the ideal consisting of those elements in R that annihilate all simple right R- modules. It happens that substituting "left" in place of "right" in the definitio ...

, consisting of those elements in a ring R that annihilate all simple right R-modules **

Nilradical of a ring In algebra, the nilradical of a commutative ring is the ideal consisting of the nilpotent elements: :\mathfrak_R = \lbrace f \in R \mid f^m=0 \text m\in\mathbb_\rbrace. In the non-commutative ring case the same definition does not always work. ...

, a nilpotent ideal which is as large as possible *

Radical of a module In mathematics, in the theory of modules, the radical of a module is a component in the theory of structure and classification. It is a generalization of the Jacobson radical for rings. In many ways, it is the dual notion to that of the socle ...

, a component in the theory of structure and classification *

Radical of an integer In number theory, the radical of a positive integer ''n'' is defined as the product of the distinct prime numbers dividing ''n''. Each prime factor of ''n'' occurs exactly once as a factor of this product: \displaystyle\mathrm(n)=\prod_p The radic ...

, in number theory, the product of the primes which divide an integer *

Radical of a Lie algebra In the mathematical field of Lie theory, the radical of a Lie algebra \mathfrak is the largest solvable ideal of \mathfrak.. The radical, denoted by (\mathfrak), fits into the exact sequence :0 \to (\mathfrak) \to \mathfrak g \to \mathfrak/(\ma ...

, a concept in Lie theory **

Nilradical of a Lie algebra In algebra, the nilradical of a Lie algebra is a nilpotent ideal, which is as large as possible. The nilradical \mathfrak(\mathfrak g) of a finite-dimensional Lie algebra \mathfrak is its maximal nilpotent ideal, which exists because the sum of ...

, a nilpotent ideal which is as large as possible *Left (or right) radical of a

bilinear form In mathematics, a bilinear form is a bilinear map on a vector space (the elements of which are called '' vectors'') over a field ''K'' (the elements of which are called '' scalars''). In other words, a bilinear form is a function that is lin ...

, the subspace of all vectors left (or right) orthogonal to every vector

Linguistics

Root (linguistics) A root (or root word) is the core of a word that is irreducible into more meaningful elements. In morphology, a root is a morphologically simple unit which can be left bare or to which a prefix or a suffix can attach. The root word is the prima ...

, also called a "radical", the form of a word after any prefixes and suffixes are removed *

Radical (Chinese characters) A Chinese radical () or indexing component is a graphical component of a Chinese character under which the character is traditionally listed in a Chinese dictionary. This component is often a semantic indicator similar to a morpheme, though ...

, part of a Chinese character *

Radical consonant A pharyngeal consonant is a consonant that is articulated primarily in the pharynx. Some phoneticians distinguish upper pharyngeal consonants, or "high" pharyngeals, pronounced by retracting the root of the tongue in the mid to upper pharynx ...

, a pharyngeal consonant *Radical, one of the three consonants in a

Semitic root The roots of verbs and most nouns in the Semitic languages are characterized as a sequence of consonants or "radicals" (hence the term consonantal root). Such abstract consonantal roots are used in the formation of actual words by adding the vowe ...

Arts and entertainment

Music

* ''Radical'' (mixtape), by Odd Future, 2010 * ''Radical'' (Every Time I Die album), 2021 * ''Radical'' (Smack album), 1988 *"Radicals", a song by Tyler, The Creator from the 2011 album ''

Goblin A goblin is a small, grotesque, monstrous creature that appears in the folklore of multiple European cultures. First attested in stories from the Middle Ages, they are ascribed conflicting abilities, temperaments, and appearances depending on t ...

Architecture and design

* Radical period (design), a period in late 1960s Italian design *

Radical Baroque Baroque architecture is a highly decorative and theatrical style which appeared in Italy in the early 17th century and gradually spread across Europe. It was originally introduced by the Catholic Church, particularly by the Jesuits, as a means t ...

, an architectural style

Literature

*'' Radical: My Journey out of Islamist Extremism'', by Maajid Nawaz, 2013 * ''Radical'' (book), by David Platt, 2010

Other uses

* Radical, Missouri, U.S., a ghost town * Radical, North Carolina, U.S. *

Radical Sportscars Radical Motorsport is a British manufacturer and constructor of racing cars. The company was founded in January 1997 by amateur drivers and engineers Mick Hyde and Phil Abbott, who built open cockpit sportscars which could be registered for roa ...

, a British sports car maker *

Radical Entertainment Radical Entertainment Inc. is a Canadian video game developer based in Vancouver. The studio is best known for developing '' The Simpsons: Hit & Run'', ''Prototype'' and ''Prototype 2'', as well as entries in the '' Crash Bandicoot'' franchise. ...

, a Canadian video game developer *

Radical.fm Radical.FM was a digital music streaming service available on iOS devices, Android devices, and desktop web browsers. The service allows users to create their own custom online radio stations based on musical genres. Unlike other streaming services ...

, a digital music streaming service