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.

---

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

---

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

Example Sentences

“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

"This partnership has improved intelligence sharing, operational coordination, and the overall effectiveness of Nigerian-led efforts against violent extremist organizations."

From Barron's • Mar. 21, 2026

They had no apparent links to international terrorist networks — until Malik pledged allegiance to the leader of the extremist group Islamic State on Facebook shortly before the attack.

From Los Angeles Times • Mar. 10, 2026

The film traces how suspicion fell in particular on several members of the Jewish Defense League, a group founded by extremist rabbi Meir Kahane before his own assassination in 1990.

From Barron's • Feb. 21, 2026

An extremist was addressing the gathering and telling them that they were fools to go on fighting, that they ought to refuse and go home, and so forth.

From Another Sheaf by Galsworthy, John

Related Words

• fanatic
• zealot