extremist

American  

[ik-stree-mist] / ɪkˈstri mɪst /

noun

1. a person who goes to extremes, especially in political matters.

2. a supporter or advocate of extreme doctrines or practices.

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adjective

1. belonging or pertaining to extremists.

extremist British  

/ ɪkˈstriːmɪst /

noun

1. a person who favours or resorts to immoderate, uncompromising, or fanatical methods or behaviour, esp in being politically radical

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adjective

1. of, relating to, or characterized by immoderate or excessive actions, opinions, etc

Other Word Forms

• extremism
  noun

Etymology

Origin of extremist

First recorded in 1840–50; extreme + -ist

Explanation

Nowadays, we tend to associate the word extremist with "terrorist," and use the two words almost interchangeably to define someone who holds radical political or religious views. An extremist can hold views on any subject: if you believe all little brothers should be banned from their siblings' rooms, or that anyone who roots for a different baseball team should be quarantined, then you, my friend, are an extremist. What tends to unite all extremists is their willingness to act, often violently, to realize their beliefs. Little brothers, watch out.

Example Sentences

Researchers are finding that extremist ideas are now spreading through looser networks where many voices contribute and messaging can vary widely.

From Salon • May 8, 2026

"Anything that creates, like an agitation, in the extremist on either side of the aisle is a frightening dynamic," Griffin said.

From BBC • May 6, 2026

Not that extremist positions should be off limits, but they ought to be more rigorously addressed.

From Los Angeles Times • Apr. 21, 2026

“They’re concerned the Middle East tensions could lead to more extremist cell activity in Western countries,” Bannister said.

From The Wall Street Journal • Mar. 31, 2026

In fact, I am, and always have been, an extremist, a purist.

From The Book of Khalid by Rihani, Ameen Fares

Related Words

• fanatic
• zealot