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adjective rad·i·cal \ˈra-di-kəl\

Simple Definition of radical

  • : 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. 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. 2 :  of or relating to the origin :  fundamental

  3. 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>

  4. 4 slang :  excellent, cool

rad·i·cal·ness noun

Examples of radical

  1. The computer has introduced radical innovations.

  2. There are some radical differences between the two proposals.

  3. The new president has made some radical changes to the company.

  4. a radical wing of extremists

Origin of radical

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

First Known Use: 14th century



noun rad·i·cal

Simple Definition of radical

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

Full Definition of radical

  1. 1 a :  a root part b :  a basic principle :  foundation

  2. 2 a :  root 6 b :  a sound or letter belonging to a radical

  3. 3 :  one who is radical

  4. 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. 5 a :  a mathematical expression indicating a root by means of a radical sign b :  radical sign

Examples of radical

  1. He was a radical when he was young, but now he's much more moderate.

  2. <radicals staged large, violent protests in the hopes of toppling the government>


First Known Use of radical


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February 7, 2016

a slight offense

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