Radical (from Latin: ', root) may refer to:

Politics and ideology

Politics

Classical radicalism Radicalism (from French ) was a political movement representing the leftward flank of liberalism between the late 18th and early 20th century. Certain aspects of the movement were precursors to a wide variety of modern-day movements, ranging f ...

, the Radical Movement that began in late 18th century Britain and spread to continental Europe and Latin America in the 19th century *

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 radic ...

, the political intent of fundamental societal change * Radical Party (disambiguation), 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 Rad ...

, 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 radical views in opposition to a political, social, or religious status quo. The ideas of society at large shape the outcomes of rad ...

*Politicians from the

Radical Civic Union The Radical Civic Union (, UCR) is a major political party in Argentina. It has reached the national government on ten occasions, making it one of the most historically important parties in the country. Ideologically, the party has stood for r ...

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

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

, 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 valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spont ...

, an atom, molecule, or ion with unpaired valence electron(s) * Radical surgery, where diseased tissue or lymph nodes are removed from a diseased organ

Mathematics

Radical expression In mathematics, an th root of a number is a number which, when raised to the power of , yields : r^n = \underbrace_ = x. The positive integer is called the ''index'' or ''degree'', and the number of which the root is taken is the ''ra ...

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

Solution in radicals A solution in radicals or algebraic solution is an expression of a solution of a polynomial equation that is algebraic, that is, relies only on addition, subtraction, multiplication, division, raising to integer powers, and extraction of ...

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

(√), used to indicate the square root and other roots *

Radical of an algebraic group The radical of an algebraic group is the identity component of its maximal normal solvable subgroup. For example, the radical of the general linear group \operatorname_n(K) (for a field ''K'') is the subgroup consisting of scalar matrices, i.e. m ...

, a concept in algebraic group theory *

Radical of an ideal Radical (from Latin: ', root) may refer to: Politics and ideology Politics * Classical radicalism, the Radical Movement that began in late 18th century Britain and spread to continental Europe and Latin America in the 19th century * Radical politi ...

, an important concept in abstract algebra * Radical of a ring, 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. It is thus the radical of the zero ideal. If the nilradical is the zero ide ...

, 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 rad ...

, 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/(\math ...

, 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 linea ...

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

Linguistics

Root (linguistics) A root (also known as a root word or radical) 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. ...

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

Radical (Chinese characters) A radical (), or indexing component, is a visually prominent Chinese character components, component of a Chinese character under which the character is traditionally listed in a Chinese dictionary. The radical for a character is typically a s ...

, 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 vowel ...

Arts and entertainment

Music

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

Dyro Jordy van Egmond (; born 22 April 1992), known professionally as Dyro ( ), is a Dutch DJ and Electronic dance music, EDM producer. Since 2010 he has released original singles and remixes on labels such as Revealed Recordings, Tiësto, Musical F ...

and

Dannic Daan Romers (; born 10 November 1985), better known by his stage name Dannic (stylized as DɅNNIC), is a Dutch people, Dutch Disc jockey, DJ and Electronic dance music, EDM record producer, producer. He is known for his work in collaborations wi ...

, 2014

Architecture and design

* Radical period (design), a period in late 1960s Italian design * Radical Baroque, an architectural style

Literature

* '' Radical: Taking Back Your Faith from the American Dream'', a 2010 book by Christian pastor David Platt * '' Radical: My Journey out of Islamist Extremism'', a 2012 memoir by British activist Maajid Nawaz

Film

* ''Radical'' (film), a 2023 Spanish language film

Other uses

* Murphy Radical, a Canadian light aircraft design * Radical, Missouri, U.S., a ghost town *

Radical Sportscars Radical Motorsport Limited, also known as Radical Sportscars, 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 s ...

, 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'' (2003), '' Scarface: The World Is Yours'' (2006), ''Prototype'' (2009) and '' Prototype 2'' (2 ...

, a Canadian video game developer * Radical.fm, a digital music streaming service * '' Radical Software'', American art journal started in 1970