radical

adjective
rad·​i·​cal | \ ˈra-di-kəl How to pronounce radical (audio) \

Definition of radical

 (Entry 1 of 2)

1 : of, relating to, or proceeding from a root: such as
a(1) : of or growing from the root of a plant radical tubers
(2) : growing from the base of a stem, from a rootlike stem, or from a stem that does not rise above the ground radical leaves
b : of, relating to, or constituting a linguistic root
c : of or relating to a mathematical root
d : designed to remove the root of a disease or all diseased and potentially diseased tissue radical surgery radical mastectomy
2 : of or relating to the origin : fundamental
3a : very different from the usual or traditional : extreme
b : favoring extreme changes in existing views, habits, conditions, or institutions
c : associated with political views, practices, and policies of extreme change
d : advocating extreme measures to retain or restore a political state of affairs the radical right
4 slang : excellent, cool

radical

noun

Definition of radical (Entry 2 of 2)

1a : a root part
b : a basic principle : foundation
b : a sound or letter belonging to a radical
3 : one who is radical
4 : free radical also : a group of atoms bonded together that is considered an entity in various kinds of reactions or as a subunit of a larger molecule
5a : a mathematical expression indicating a root by means of a radical sign

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Other Words from radical

Adjective

radicalness noun

Examples of radical in a Sentence

Adjective The computer has introduced radical innovations. There are some radical differences between the two proposals. The new president has made some radical changes to the company. a radical wing of extremists Noun He was a radical when he was young, but now he's much more moderate. radicals staged large, violent protests in the hopes of toppling the government
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Recent Examples on the Web: Adjective If abused, such a law could be used against those with viewpoints, however radical, protected by the First Amendment. Alex Connor, USA TODAY, "Happy New(s) Year Eve," 31 Dec. 2019 The demands of the people were getting increasingly urgent and radical. Mikhail Gorbachev, Time, "Mikhail Gorbachev: "In 1989 the World Chose Peace; We Need That Vision Today"," 31 Oct. 2019 Besieged from all sides by folks with the crazy-radical idea that workers producing billions of dollars should benefit from their toils, the Double-A is yielding. Paul Daugherty, Cincinnati.com, "Doc's Morning Line: That was a terrific World Series and I'm sick of the Bengals right now," 31 Oct. 2019 Widespread defiance of the mask ban and the solid turnout for Monday’s rally suggested that Lam’s government is barely making headway with its efforts to get demonstrators to turn their back on the movement’s more radical and destructive hardcore. John Leicester, San Diego Union-Tribune, "Hong Kong police say homemade bomb targeted officers," 14 Oct. 2019 Ellencweig said, a radical departure from the conventional wisdom about what shoppers focus on. Mark Phelan, chicagotribune.com, "High-end buyers are changing what they want in a vehicle. Here’s why automakers are complying," 6 Dec. 2019 And more radical ideas — like an outright ban on jailhouse informants in capital cases — have stalled, allowing prosecutors to continue using snitch testimony to secure the starkest, most irrevocable punishment. Pamela Colloff, ProPublica, "He’s a Liar, a Con Artist and a Snitch. His Testimony Could Soon Send a Man to His Death.," 4 Dec. 2019 Gopnik’s proposal is a radical departure from how researchers typically get a robot to learn. Matt Simon, Wired, "The Case for Sending Robots to Day Care, Like Toddlers," 26 Nov. 2019 At a time when female Latin stars are in scant supply, Rosalía became a sensation-fusing high-concept artist with hip-hop beats and visual imagery to create a compelling album that was also a radical departure, for any language or genre. Billboard Staff, Billboard, "The 100 Greatest Albums of the 2010s: Staff Picks," 19 Nov. 2019 Recent Examples on the Web: Noun In 1991, radicals in Lebanon released American hostage Alann Steen, who’d been held captive nearly five years. BostonGlobe.com, "You're using a browser set to private or incognito mode.," 3 Dec. 2019 That support stretched beyond his base to other minority sects in Syria and some middle- and upper-class Sunnis who regard his family rule as a bulwark of stability in the face of Islamic radicals. Sarah El Deeb, The Seattle Times, "Syria’s Assad: Last man standing amid new Arab uprisings," 13 Apr. 2019 In the ’20s and ’30s, there were millions of radicals in the United States. Todd Vanderwerff, Vox, "100 years of the American left in 5 minutes, with Sorry to Bother You director Boots Riley," 27 July 2018 From the outset, the occupation presented a public relations crisis for the administration: negotiate with armed radicals, or risk a deadly firefight at the site of the most infamous massacre in American history. Julian Brave Noisecat, Harper's magazine, "Perhaps the World Ends Here," 5 Dec. 2019 The Emirati leadership views Islah as a threat because of its links to the Muslim Brotherhood, a regional Islamist movement that the Emiratis and their allies see as radicals. Washington Post, "Six reasons the crisis in Yemen’s south matters," 30 Aug. 2019 Beijing has criticized some protesters as violent radicals spurred on by foreign forces bent on containing China’s development. Yanan Wang, BostonGlobe.com, "Hong Kong protesters march despite police ban," 10 Aug. 2019 Frustrated by the absence of clear choices, many turn to radicals and populists. Washington Post, "Germany’s Crisis Has Been Averted. But at What Cost?," 6 Dec. 2019 Post knew, and had published, many of the leading reformers and radicals of the day. Adam Hochschild, The New Yorker, "When America Tried to Deport Its Radicals," 4 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radical.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of radical

Adjective

14th century, in the meaning defined at sense 1

Noun

1641, in the meaning defined at sense 1a

History and Etymology for radical

Adjective

Middle English, from Late Latin radicalis, from Latin radic-, radix root — more at root

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Time Traveler for radical

Time Traveler

The first known use of radical was in the 14th century

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Statistics for radical

Last Updated

7 Jan 2020

Cite this Entry

“Radical.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/radical. Accessed 19 January 2020.

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More Definitions for radical

radical

adjective
How to pronounce radical (audio)

English Language Learners Definition of radical

 (Entry 1 of 2)

: very new and different from what is traditional or ordinary
: very basic and important
: having extreme political or social views that are not shared by most people

radical

noun

English Language Learners Definition of radical (Entry 2 of 2)

: a person who favors extreme changes in government : a person who has radical political opinions

radical

adjective
rad·​i·​cal | \ ˈra-di-kəl How to pronounce radical (audio) \

Kids Definition of radical

 (Entry 1 of 2)

1 : very new and different from the usual or ordinary : extreme a radical change
2 : of or relating to people who favor rapid and sweeping changes in laws and government

Other Words from radical

radically adverb

radical

noun

Kids Definition of radical (Entry 2 of 2)

: a person who favors rapid and sweeping changes especially in laws and government

radical

adjective
rad·​i·​cal | \ ˈrad-i-kəl How to pronounce radical (audio) \

Medical Definition of radical

 (Entry 1 of 2)

1 : designed to remove the root of a disease or all diseased tissue radical surgery
2 : involving complete removal of an organ radical prostatectomy — compare conservative

Other Words from radical

radically \ -​i-​k(ə-​)lē How to pronounce radically (audio) \ adverb

radical

noun

Medical Definition of radical (Entry 2 of 2)

: free radical also : a group of atoms bonded together that is considered an entity in various kinds of reactions

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Comments on radical

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