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radical

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adjective rad·i·cal \ˈra-di-kəl\

Definition of radical

  1. 1 :  of, relating to, or proceeding from a root: such asa (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 leavesb :  of, relating to, or constituting a linguistic rootc :  of or relating to a mathematical rootd :  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. 3a :  very different from the usual or traditional :  extremeb :  favoring extreme changes in existing views, habits, conditions, or institutionsc :  associated with political views, practices, and policies of extreme changed :  advocating extreme measures to retain or restore a political state of affairs the radical right

  4. 4 slang :  excellent, cool

radicalness

noun

Examples of radical in a Sentence

  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

Recent Examples of radical from the Web

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.

Origin and Etymology of radical

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


2

radical

noun rad·i·cal

Definition of radical

  1. 1a :  a root partb :  a basic principle :  foundation

  2. 2a :  root 6b :  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. 5a :  a mathematical expression indicating a root by means of a radical signb :  radical sign

Examples of radical in a Sentence

  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

Recent Examples of radical from the Web

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.

First Known Use of radical

1641


RADICAL Defined for English Language Learners

radical

play
adjective

Definition of radical for English Language Learners

  • : 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

Definition of radical for English Language Learners

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


RADICAL Defined for Kids

1

radical

play
adjective rad·i·cal \ˈra-di-kəl\

Definition of radical for Students

  1. 1 :  very new and different from the usual or ordinary :  extreme a radical change

  2. 2 :  of or relating to people who favor rapid and sweeping changes in laws and government

radically

adverb

2

radical

play
noun rad·i·cal

Definition of radical for Students

  1. :  a person who favors rapid and sweeping changes especially in laws and government


Medical Dictionary

1

radical

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adjective rad·i·cal \ˈrad-i-kəl\

Medical Definition of radical

  1. 1:  designed to remove the root of a disease or all diseased tissue radical surgery

  2. 2:  involving complete removal of an organ radical prostatectomy—compare conservative

radically

\-i-k(ə-)lē\play adverb

2

radical

noun rad·i·cal

Medical Definition of radical

  1. :  free radical; also :  a group of atoms bonded together that is considered an entity in various kinds of reactions



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