terrorist

UK: /ˈtɛrərɪst/ US: (ter′ər ist)

WordReference Random House Unabridged Dictionary of American English © 2025

ter•ror•ist  (ter′ər ist), n. 

1. Government a person, usually a member of a group, who uses or advocates terrorism.
2. Government a person who terrorizes or frightens others.
3. Government (formerly) a member of a political group in Russia aiming at the demoralization of the government by terror.
4. Government an agent or partisan of the revolutionary tribunal during the Reign of Terror in France.

adj. 

5. Government of, pertaining to, or characteristic of terrorism or terrorists:
   terrorist tactics.

• 1785–95; terror + -ist; compare French terroriste

ter′ror•is′tic, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

terrorist / ˈtɛrərɪst/ noun

1. a person who employs terror or terrorism, esp as a political weapon
2. (as modifier): terrorist tactics

WordReference Random House Learner's Dictionary of American English © 2025

ter•ror•ism /ˈtɛrəˌrɪzəm/   n. [uncountable]

1. Government the use of violence and threats to frighten and force one's will on another, esp. for political purposes.

ter•ror•ist, n. 

[countable] terrorists who were active in the overthrow of the government.

—adj. 

: terrorist activities.

WordReference Random House Unabridged Dictionary of American English © 2025

ter•ror•ism  (ter′ə riz′əm), n. 

1. Government the use of violence and threats to intimidate or coerce, esp. for political purposes.
2. Government the state of fear and submission produced by terrorism or terrorization.
3. Government a terroristic method of governing or of resisting a government.

• terror + -ism 1785–95