radical

adjective
rad·​i·​cal | \ ˈra-di-kəl \

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

Any trade with Iran means a benefit for radical and terrorist forces and a hazard and destabilization for the region. Benjamin Weinthal, Fox News, "Germany accused of betraying pledge to combat anti-Semitism by ignoring Iran sanctions," 22 Aug. 2018 Mari's anti-gentrification group, Vigilantes de Los Angeles, resembles in some ways the neighborhood's Defend Boyle Heights activist group, which has been described as radical and militant. Alejandra Reyes-velarde, latimes.com, "Starz’s ‘Vida’ puts the spotlight on gentrification and brown queerness in Boyle Heights," 4 May 2018 In a February statement, Lee argued that Feldblum was too radical for the EEOC, casting her as an opponent of religious freedom. Anna North, Vox, "Conservative Sen. Mike Lee is holding up a Trump nominee for supporting LGBTQ rights," 18 Dec. 2018 Titled EcoTerror, it is named, in part, after a radical environmental movement that began in the 1960s. Noor Brara, Vogue, "With Her Debut Collection, Sami Miro Is Using Vintage Fashion to Help Save the Planet," 8 Nov. 2018 Embrace this lunar energy, because the very next day, a radical shift occurs in the sky. Aliza Kelly Faragher, Allure, "What November's Capricorn Horoscope Means for You," 28 Oct. 2018 The radical inclusion is made possible by these secret escape hatches. Jonathon Keats, Discover Magazine, "The Vanishing City," 13 Aug. 2018 Sierra Nevada’s approach is fairly radical—the Air Force doesn’t like buying second hand planes, but the aircraft will essentially be new, inexpensive, and not saddled with older, more expensive to maintain systems. Kyle Mizokami, Popular Mechanics, "The Air Force Wants Helicopters to Help Defend Nuclear Missiles," 10 Aug. 2018 After taking power in June 2018, the populist coalition, combining the Northern League and the radical Five Star Movement (M5S), started its own battle with the EU, also on the subject of migration. The Economist, "Breaking point: December 2020," 5 July 2018

Recent Examples on the Web: Noun

The group organized or inspired a spate of attacks on French soil, including the November 2015 massacre of 130 people in Paris, and its Syrian presence was a common destination for Islamist radicals from France. Sam Schechner, WSJ, "French Police Hunt for Gunman in Strasbourg Attack," 12 Dec. 2018 This is putting into effect our policy of zero tolerance toward far-right radicals and right-wing extremists. Bojan Pancevski, WSJ, "German Police Arrest Six Suspected Neo-Nazis Ahead of Alleged Planned Attack," 1 Oct. 2018 Going on from that, radicals and revolutionaries had been hoping that the US would get involved in fighting Hitler. Todd Vanderwerff, Vox, "100 years of the American left in 5 minutes, with Sorry to Bother You director Boots Riley," 27 July 2018 Cultural radicals from the era like Alice Schwarzer, a feminist commentator, are now part of the talk-show establishment. The Economist, "The legacy of Germany’s student protests in 1968," 31 May 2018 The suspect, who is married to a German woman, allegedly was in contact with Islamic radicals and twice tried to travel to Syria last year, investigators said. Frank Jordans, chicagotribune.com, "Tip from public helped Germany foil ricin attack plot," 20 June 2018 Tariq Ali edited the Black Dwarf and then the Red Mole (Marxist papers which—perhaps oddly, given their influence with British radicals of the era—are not discussed in much detail). The Economist, "1968 was no mere year," 5 Apr. 2018 Saudi rulers were handling the hardware, while radicals rewrote the nation’s software. Adel Al-toraifi, WSJ, "The Saudis Take On Radical Islam," 19 Mar. 2018 Among them were Democrats and Republicans, radicals and conservatives, rabble rousers and club women, the flamboyant and the staid. Fergus M. Bordewich, WSJ, "‘The Woman’s Hour’ Review: Friends and Foes of the 19th Amendment," 21 June 2018

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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Statistics for radical

Last Updated

21 Jan 2019

Look-up Popularity

Time Traveler for radical

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

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More Definitions for radical

radical

adjective

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 \

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 \

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 \ 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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