radical

radical — adjective

IPA/ˈrædɪkl/
KK[rˈædəkəl]IPA/ˈrædɪkl/
  • radicalpositive
  • more radicalcomparative
  • most radicalsuperlative

1. holding or expressing a strong desire for major changes in the political or soci

1.adjectiveC2
Definition

holding or expressing a strong desire for major changes in the political or social systems of a country, often changes that seem extreme to other people.

Example

Jiwoo's political views became more radical after she saw the living conditions in the city.

radical + views for extreme political beliefs

The group published a radical newspaper that called for the end of the monarchy.

Common collocations
  • radical views
  • radical ideas
  • radical group
  • radical movement
  • radical activist
  • radical politics
Synonyms
  • extreme

    focuses on degree of departure from the norm, often with negative tone

  • revolutionary

    suggests aiming to completely overthrow existing institutions

  • progressive

    milder and generally positive, supporting gradual improvement

Antonyms
  • conservative

    prefers to keep existing systems and avoid major change

  • moderate

    avoids extreme positions, seeks middle ground

Grammar Patterns

radical + noun (views, ideas, group, activist)

Usage Note

Commonly applied to people, movements, or policies that advocate extreme social or political reform. The connotation varies: some speakers use it negatively to mean 'unreasonably extreme,' while others use it positively to mean 'courageously progressive.'

Common Mistakes

The radical government raised taxes by 2%.
The radical government completely replaced the tax system.
Radical implies extreme, fundamental change, not small adjustments.

2. touching the deepest or most central parts of something, usually producing chang

2.adjectiveC1
Definition

touching the deepest or most central parts of something, usually producing change that is complete in scope and affects the whole system.

Example

The company made radical changes to its business model after losing money for two years.

radical + changes for complete restructuring

Yara's research led to a radical new understanding of how young children learn language.

Common collocations
  • radical change
  • radical reform
  • radical difference
  • radical shift
  • radical overhaul
  • radical new
Synonyms
  • fundamental

    focuses on basic principles without necessarily implying extreme action

  • drastic

    emphasizes urgency and severity of the action taken

  • sweeping

    suggests wide-ranging coverage affecting many areas at once

  • thorough

    highlights completeness and attention to all parts

Antonyms
  • superficial

    only affecting the surface, not the core

  • minor

    small in scale or importance

Grammar Patterns

radical + noun (change, reform, difference, shift)

Usage Note

Often precedes nouns like change, reform, difference, shift, or overhaul. The focus is on either the depth of analysis (going to the root) or the extent of transformation (affecting the whole system).

Common Mistakes

We made a radical improvement to the website colour.
We made a radical improvement by rebuilding the entire website.
Radical must imply a complete or fundamental change, not a minor adjustment.

3. describing a medical procedure that aims to completely remove all diseased or da

3.adjective
Definition

describing a medical procedure that aims to completely remove all diseased or damaged tissue, rather than just treating the symptoms.

Example

The doctors recommended radical surgery to remove the entire tumour from Ramón's lung.

radical surgery for complete removal of diseased tissue

After the diagnosis, Mira had to decide whether to undergo a radical mastectomy.

Common collocations
  • radical surgery
  • radical treatment
  • radical operation
  • radical mastectomy
  • radical procedure
Synonyms
  • complete

    less specific, means total removal without the technical medical tone

  • total

    used interchangeably with radical in some surgical contexts, e.g. total mastectomy

Grammar Patterns

radical + surgery / treatment / operation / mastectomy

Usage Note

Used exclusively in medical contexts, typically before surgery, treatment, operation, mastectomy, or procedure. It is NOT interchangeable with 'severe' or 'aggressive' — 'radical' specifically means removing the root cause completely.

Common Mistakes

The doctor gave me a radical injection for the pain.
The surgeon performed a radical mastectomy to remove all the cancerous tissue.
Radical in medicine refers to complete removal of tissue, not to strong medication.

4. extremely good, impressive, or enjoyable in a way that excites or pleases people

4.adjective
Definition

extremely good, impressive, or enjoyable in a way that excites or pleases people.

Example

Anjali said the concert was absolutely radical, especially the guitar solos.

informal slang: be + radical for 'excellent'

The skateboard video showed some radical tricks that the crowd loved.

Synonyms
  • awesome

    still current slang, wider use than radical

  • cool

    broad slang meaning good/impressive, very common

  • sick

    current youth slang for excellent, especially in sports

Antonyms
  • terrible

    strongly negative evaluation

  • lame

    slang antonym meaning unimpressive or boring

Grammar Patterns

Subject + be + radical

radical + noun (trick, concert, party)

Usage Note

Slang usage that peaked in the 1980s—1990s within surfer, skateboard, and youth subcultures. Still understood by most English speakers but sounds dated; younger speakers today are more likely to use awesome, sick, or dope.

Common Mistakes

The weather today is radical.' (trying to say 'very good').
That skateboard trick was radical!
This slang sense is typically used for impressive actions or performances, not for everyday phenomena like weather.

radical — noun

IPA/ˈræd.ɪ.kəl/
KK[rˈædəkəl]IPA/ˈræd.ɪ.kəl/

Word family

Synonym discussion

Sense: adjective/1

Extreme focuses on how far something is from the norm and often carries a negative tone, suggesting that the views are unreasonable. Revolutionary implies a desire to completely overthrow existing systems and replace them with entirely new ones. Militant suggests a willingness to use forceful or confrontational methods, including protest or direct action. Progressive is a much milder term, describing support for gradual social improvement within existing structures — a progressive might advocate for higher taxes on the wealthy, while a radical would demand the abolition of private property entirely. To illustrate: a radical politician calls for abolishing the current constitution; a progressive calls for amending it slowly.

extreme ↗revolutionary ↗militant ↗progressive ↗

Common collocations

Adverbs

  • radically

Phrases

  • radical approach
  • radical idea
  • radical opinion

Etymology

LatinLate LatinFrenchEnglish

Radical comes from the Latin word radix, meaning 'root.' In Late Latin, radicalis described something 'of or relating to a root.' English first used radical in the 14th century with the literal meaning of 'forming a root' or 'relating to roots.' By the 17th century, it had developed the figurative meaning of 'going to the origin or foundation.' The political sense — supporting extreme reform by addressing the 'root' of social problems — emerged in the early 1800s during the British reform movements. The informal slang meaning 'excellent' appeared in American English in the 1970s—1980s, popularized by surfer and skateboard subcultures.