Radical means pertaining to roots, or at or in the roots. It is derived from the Latin word radix, which means "root". It may refer to:

In mathematics:

• The radical symbol used to indicate the nth root of a number a, written as $\backslash sqrt*\{a\}$, which is a number whose n-th power is a
• Radical of an algebraic group, a concept in algebraic group theory
• Radical of an ideal, an important concept in abstract algebra
• Radical of an integer, a concept in number theory

In science:

• Radical (chemistry), atomic or molecular species with unpaired electrons

In linguistics:

• Radical consonant, involves the root of the tongue
• Radical (Chinese character), in grammatology, part of a Chinese character

In politics:

• Radicalism, any of various ideologies or political groupings
• a supporter of a revolutionary social movement, opposed to liberalism and conservatism, particularly a supporter of libertarian socialism or the far-left
  • a supporter of the "radical right" variety of the far right
  • a neoconservative
  • a supporter of the Radical Left
  • The term radical is used by the right wing in the United States to mischaracterise elements of the Democratic Party
• Radicalization, which refers to the transformation from passiveness or activism to more revolutionary, extremist, or militant postures. While the term "radical" can be commonly associated with far-left movements, "radicalization" makes no such distinction.

• a supporter of Radicalism (historical), a movement which developed in 18th and 19th century Britain with aims including electoral reform and republicanism, and subsequent leftist liberal movements in continental Europe and Latin America
  • Radical Whigs, influential early writers on Radicalism
• a Radical Republican (an influential group of American politicians during the Civil War reconstruction)
• a Radical Party member
• a supporter of Radicals (UK), parliamentary progressives who were predecessors of the Liberal Party (UK)

In commerce:

• Radical Sportscars or Radical Motorsport, sports car maker in England
• Free Radical Design, a video game developer based in Nottingham, England

See also

• Radicle

Radikal | Radical | Radical | Radiko | Radicaal | Radical | Радикал | Radikal (samhällsvetenskap)