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radical
[ rad-i-kuhl ]
/ ˈræd ɪ kəl /
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adjective
noun
OTHER WORDS FOR radical
VIDEO FOR RADICAL
Do You Remember This Radical 80s Slang?
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ALL IN FAVO(U)R OF THIS BRITISH VS. AMERICAN ENGLISH QUIZ
There's an ocean of difference between the way people speak English in the US vs. the UK. Are your language skills up to the task of telling the difference? Let's find out!
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True or false? British English and American English are only different when it comes to slang words.
Origin of radical
synonym study for radical
2. Radical, extreme, fanatical denote that which goes beyond moderation or even to excess in opinion, belief, action, etc. Radical emphasizes the idea of going to the root of a matter, and this often seems immoderate in its thoroughness or completeness: radical ideas; radical changes or reforms. Extreme applies to excessively biased ideas, intemperate conduct, or repressive legislation: to use extreme measures. Fanatical is applied to a person who has extravagant views, especially in matters of religion or morality, which render that person incapable of sound judgments; and excessive zeal which leads him or her to take violent action against those who have differing views: fanatical in persecuting others.
historical usage of radical
Radical comes straight from the Late Latin adjective rādicālis “having roots, rooted,” first occurring about a.d. 400 in Contra Faustum (“Against Faustus the Manichaean”) by St. Augustine of Hippo. Rādicālis is a derivative of the noun rādix (inflectional stem rādīc- ) “root (of a plant, tooth, hair), root (of a family, stock, breed), (etymological) root.” The mathematical sense “denoting the radical sign which indicates the root of a number” dates from the late 17th century. Radical in its political sense dates from the late 18th century in England and the first half of the 19th century in the United States.
Latin rādix comes from wrād-, one of the variants of the Proto-Indo-European root wrād, werād, wred- “root, branch.” From this same variant Latin also has rāmus “branch” (the root, so to speak, of English ramify ); Greek has rhádix (stem rhádik- ) from the same variant. Another variant of the root is the possible source of Greek rhiza, source of English rhizome (Greek variants include Aeolic briza, brisda and Mycenaean wriza ). Wrād- regularly becomes wrōt- in proto-Germanic, the ultimate source of the English word root.
Latin rādix comes from wrād-, one of the variants of the Proto-Indo-European root wrād, werād, wred- “root, branch.” From this same variant Latin also has rāmus “branch” (the root, so to speak, of English ramify ); Greek has rhádix (stem rhádik- ) from the same variant. Another variant of the root is the possible source of Greek rhiza, source of English rhizome (Greek variants include Aeolic briza, brisda and Mycenaean wriza ). Wrād- regularly becomes wrōt- in proto-Germanic, the ultimate source of the English word root.
OTHER WORDS FROM radical
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Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use radical in a sentence
British Dictionary definitions for radical
radical
/ (ˈrædɪkəl) /
adjective
noun
Derived forms of radical
radicalness, nounWord Origin for radical
C14: from Late Latin rādīcālis having roots, from Latin rādix a root
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Scientific definitions for radical
radical
[ răd′ĭ-kəl ]
A root, such as √2, especially as indicated by a radical sign (√).
A group of atoms that behaves as a unit in chemical reactions and is often not stable except as part of a molecule. The hydroxyl, ethyl, and phenyl radicals are examples. Radicals are unchanged by chemical reactions.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for radical (1 of 2)
radical
In politics, someone who demands substantial or extreme changes in the existing system.
Cultural definitions for radical (2 of 2)
radical
In chemistry, an atom or group of atoms that has at least one electron free to participate in forming a chemical bond.
notes for radical
In general, radicals are associated with chemical reactions that proceed rapidly.
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.