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

Yet pride’s history is a story of a radical break with right-wing and even middle-of-the-road gay and trans politics. Laurie Marhoefer, Quartz, "From gay Nazis to “we’re here, we’re queer”: A century of arguing about gay pride," 20 June 2019 The Ball and House community and radical beauty politics, and celebrating their contributions to culture. Shalwah Evans, Essence, "This House of Hair BTS Video of Sinia Braxton Is Making Our Wednesday," 19 June 2019 According to the Wall Street Journal, YouTube is considering taking radical action by removing these children's videos and moving them to the little used YouTube Kids app. Jefferson Graham, USA TODAY, "YouTube has a kids problem and it's not going away," 19 June 2019 Dworkin was of course not the only radical feminist to write about rape and battery. Elaine Blair, The New York Review of Books, "Fighting for Her Life," 17 June 2019 For the union bosses to suggest that’s some radical concept is ridiculous. Talal Ansari, WSJ, "West Virginia Considers Bill Penalizing Teachers Who Strike," 17 June 2019 An Anthology, coined terms for two types of monogamy: reflexive and radical. Zachary Zane, Allure, "Being in a Polyamorous Relationship Prepared Me for Monogamy," 17 June 2019 Organizers were forced into a radical change of venue: a racetrack on the outskirts of Barcelona. Judy Cantor-navas, Billboard, "Doctor Music Festival Canceled After Move From Mountain Pastures to Barcelona Racetrack," 14 June 2019 But the leading candidates for the Tory leadership (and thus our country’s prime minister) not only hold some of the most shocking records on women’s rights, but are actively pursuing a radical Brexit policy which will be catastrophic for women. Phoebe Potter, refinery29.com, "Tory Leadership Candidates Calling Themselves "Feminist" Is Meaningless," 10 June 2019

Recent Examples on the Web: Noun

But such radicals also invoke loopholes to get around this rule. Mohammad Hassan Khalil, The Conversation, "So, what really is jihad?," 20 June 2019 Religious refugees, non-believers, new-comers, old-timers, traditionalists and radicals. John Adamian, courant.com, "Drive-by Truckers report on the state of America at Infinity Hall," 14 June 2019 Going forward, American suffragists largely strove to conform to fashion rather than upending it, rebranding themselves as respectable women instead of radicals. Kimberly Chrisman-campbell, The Atlantic, "When American Suffragists Tried to ‘Wear the Pants’," 12 June 2019 The eight men and one woman who detonated bombs on Easter Sunday, killing themselves and more than 250 others, were a collection of Islamist radicals including a quiet truck driver and a foreign-educated engineer. Ben Otto, WSJ, "Sri Lanka Identifies All Nine Easter Bombers," 1 May 2019 Now, memories of the events serve as a warning about the dangers of the police state, and reminder of the price that black radicals have paid in their fight for liberation. Kim Kelly, Teen Vogue, "The History of the Black Radical Group MOVE and Its Infamous Bombing by Police," 17 May 2019 One summer night in 1935, a dozen American radicals boarded a German luxury liner in New York Harbor, tore loose the swastika flag from her bow and threw it into the Hudson River. Richard Snow, WSJ, "‘The Agitator’ Review: You Can’t Fly That Flag Here!," 22 Mar. 2019 The audience is introduced to his character through the memories of an older Joan, played by Judi Dench, as she's being questioned about her experiences with political radicals at Cambridge, and her alleged work as a KGB spy during WWII. Caroline Hallemann, Town & Country, "Watch Victoria's Tom Hughes in an Exclusive New Clip of the WWII Spy Drama Red Joan," 19 Apr. 2019 Coming after a series of terrorist attacks in France by Islamist radicals, the crash spurred worries that one of them had exploited a security flaw at Charles de Gaulle airport in Paris and slipped a bomb on the plane. Andy Pasztor, WSJ, "French Investigators, Countering Egypt, Say Fire Likely Caused EgyptAir Crash," 7 July 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

24 Jun 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 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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