radical

/ˈrædɪkl/ (bre, ipa) · /ˈrædɪkl/ (ame, ipa) · /ˈra-di-kəl/ (ame, mw) · /ˈræd.ɪ.kəl/ (bre, ipa) · /ˈræd.ɪ.kəl/ (ame, ipa)

radical — adjective

  • radicalpositive
  • more radicalcomparative
  • most radicalsuperlative

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

1.形容詞C2
釋義

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.

例句

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.

同義詞
  • 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

反義詞
  • conservative

    prefers to keep existing systems and avoid major change

  • moderate

    avoids extreme positions, seeks middle ground

文法句型

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

用法筆記

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.'

常見錯誤

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.形容詞C1
釋義

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

例句

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.

同義詞
  • 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

反義詞
  • superficial

    only affecting the surface, not the core

  • minor

    small in scale or importance

文法句型

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

用法筆記

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).

常見錯誤

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.形容詞
釋義

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

例句

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.

同義詞
  • complete

    less specific, means total removal without the technical medical tone

  • total

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

文法句型

radical + surgery / treatment / operation / mastectomy

用法筆記

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.

常見錯誤

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.形容詞
釋義

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

例句

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.

同義詞
  • 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

反義詞
  • terrible

    strongly negative evaluation

  • lame

    slang antonym meaning unimpressive or boring

文法句型

Subject + be + radical

radical + noun (trick, concert, party)

用法筆記

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.

常見錯誤

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