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

Example Sentences

"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

Or one could argue the opposite: The presence of a unifying caliph might have, as it had for centuries, moderated the expansion of marginal extremist movements such as Wahhabism or, in our time, Islamic State.

From The Wall Street Journal • Mar. 4, 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

No one can charge me with being an extremist.

From From Crow-Scaring to Westminster; an Autobiography by George Edwards M.P. O.B.E.

Related Words

• fanatic
• zealot