First Known Use: 14th century
Dictionary
1radical
adjective rad·i·cal \ˈra-di-kəl\
: 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
Full Definition of RADICAL
1
: of, relating to, or proceeding from a root: 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
3
a : 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>
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Origin of RADICAL
Middle English, from Late Latin radicalis, from Latin radic-, radix root — more at root
Related to RADICAL
- Synonyms
- extremist, fanatic (or fanatical), rabid, extreme, revolutionary, revolutionist, ultra
2radical
noun
: a person who favors extreme changes in government : a person who has radical political opinions
Full Definition of RADICAL
1
a : a root part b : a basic principle : foundation
2
a : root 6 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
5
a : a mathematical expression indicating a root by means of a radical sign b : radical sign
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First Known Use of RADICAL
1641
Related to RADICAL
- Synonyms
- crazy, extremist, revolutionary, revolutionist
- Antonyms
- middle-of-the-roader, moderate
RADICALNESS Defined for Kids
1radical
adjective rad·i·cal \ˈra-di-kəl\
Definition of RADICAL for Kids
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
— rad·i·cal·ly adverb
2radical
noun
Definition of RADICAL for Kids
: a person who favors rapid and sweeping changes especially in laws and government
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