radicalism

American  

[rad-i-kuh-liz-uhm] / ˈræd ɪ kəˌlɪz əm /

noun

1. extreme views or practices, or the tendency to favor them, as in politics or religion; extremism.

   In the long term, the peace we seek will only be achieved by eliminating the conditions that feed radicalism and ideologies of violence.

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radicalism British  

/ ˈrædɪkəˌlɪzəm /

noun

1. the principles, desires, or practices of political radicals

2. a radical movement, esp in politics

3. the state or nature of being radical, esp in politics

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Other Word Forms

• antiradicalism noun
• radicalistic adjective
• radicalistically adverb

Etymology

Origin of radicalism

First recorded in 1810–20; radical + -ism

Explanation

In political science, the term radicalism is the belief that society needs to be changed, and that these changes are only possible through revolutionary means. Most people think of left-wing politics when they use the noun radicalism, although people on both ends of the spectrum can be described as radical. The word radicalism comes from the Latin radicalis, "of or having roots," which in turn arose from radix, or "root." Both radical and radicalism came out of the idea that political change must "come from the root," or the very basic source of society.

Example Sentences

Real radicalism is accepting the discomfort; it’s acknowledging that two or more things can coexist, and addressing all of those facets at once, even if the result isn’t perfect.

From Salon • Apr. 3, 2026

These prisons and camps "are hotbeds of radicalism", said Laurence Bindner, a specialist of radicalisation online.

From Barron's • Jan. 21, 2026

He was a political progressive who abhorred radicalism, an antimonopolist who recognized the inevitability of large corporations and chose to regulate rather than ban them.

From The Wall Street Journal • Dec. 29, 2025

It operates at the intersections of pop art and high-ish art, of the sacred and profane, of radicalism and die-hardism.

From Los Angeles Times • Dec. 1, 2025

It instilled a spirit of defiance and radicalism among the people, broke the fear of prison, and boosted the popularity and influence of the NIC and TIC.

From "Long Walk to Freedom" by Nelson Mandela