Radical

Radical may refer to:

Politics

 * Radicalism (historical), the Radical Movement that began in late 19th century
 * 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 politics, the political intent of fundamental societal change
 * Radical Party (disambiguation), several political parties
 * Radicals (UK), a British and Irish grouping in the early to mid-19th century
 * Radicalization
 * Politicians from the Radical Civic Union

Ideologies

 * Radical chic, 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, or Islamic extremism
 * Radical Christianity
 * Radical veganism, a radical interpretation of veganism, usually combined with anarchism
 * Radical Reformation, an Anabaptist movement concurrent with the Protestant Reformation

Science

 * Radical (chemistry), 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 involving roots, also known as an nth root
 * Radical symbol (√), used to indicate the square root and other roots
 * Radical of an algebraic group, a concept in algebraic group theory
 * Radical of an ideal, an important concept in abstract algebra
 * Radical of a ring, an ideal of "bad" elements of a ring
 * Jacobson radical, consisting of those elements in a ring R that annihilate all simple right R-modules
 * Nilradical of a ring, a nilpotent ideal which is as large as possible
 * Radical of a module, a component in the theory of structure and classification
 * Radical of an integer, in number theory, the product of the primes which divide an integer
 * Radical of a Lie algebra, a concept in Lie theory
 * Nilradical of a Lie algebra, 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), also called a "radical", the form of a word after any prefixes and suffixes are removed
 * Radical (Chinese characters), part of a Chinese character
 * Radical consonant, a pharyngeal consonant
 * Radical, one of the three consonants in a Semitic root

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

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, a British sports car maker
 * Radical Entertainment, a Canadian video game developer
 * Radical.fm, a digital music streaming service
 * Radical Software, American art journal started in 1970