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 radica ...

, 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), several political parties * Radicals (UK), 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 Radical chic is the fashionable practice of upper-class people associating with politically radical people and causes. Coined in the 1970 article "Radical Chic: That Party at Lenny's" by journalist Tom Wolfe, the term has become widely used in l ...

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

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

, 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 roo ...

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 It ...

(√), 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 called ' ...

, 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 definition y ...

, 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. Th ...

, 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 s ...

, 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/(\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 ...

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

, 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 vowels ...

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 ...

Architecture and design

Radical period (design) In Italian design, the Radical period took place in the late 1960s, with a shift in style among the avant-garde. Probably the most notable result of this avant-garde period is the installation called "Superarchitettura", made in Pistoia in 1966. Ano ...

, a period in late 1960s Italian design * Radical Baroque, 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, a digital music streaming service