aggressor

noun

ag·​gres·​sor ə-ˈgre-sər How to pronounce aggressor (audio)
Synonyms of aggressornext
: one that commits or practices aggression

Synonyms of aggressor

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Examples of aggressor in a Sentence

Each country accused the other of being the aggressor. a group of smaller states had formed an alliance to deter potential aggressors
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
There, Williams published a newsletter, The Crusader, to encourage Black people to engage in self-defense rather than nonviolence, whether during civil rights protests or confronting racist aggressors. — Aaron Coy Moulton, The Conversation, 7 Aug. 2026 The conduct of the Ukrainian military has never been seriously contested, and most Americans agree that Moscow is the aggressor and that Kyiv is fighting a just war with important geopolitical consequences. — Dafna H. Rand, Foreign Affairs, 4 Aug. 2026 The suspect's attorney said Britt was the aggressor, headbutting and swinging his belt at Fitzsimmons when he got involved. — Tara Lynch, CBS News, 4 Aug. 2026 Rogers previously served in a space aggressors unit in the US Air Force, taking up against US space operators in war game and military exercises. — Stephen Clark, ArsTechnica, 30 July 2026 See All Example Sentences for aggressor

Word History

Etymology

borrowed from Latin, "attacker, assailant," from aggredī, adgredī "to approach, attack" + -tor, agent suffix — more at aggress

First Known Use

1585, in the meaning defined above

Time Traveler
The first known use of aggressor was in 1585

Rhymes for aggressor

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Browse Nearby Words

aggressiveness
aggressor
aggrievance
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Cite this Entry

“Aggressor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aggressor. Accessed 8 Aug. 2026.

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Kids Definition

aggressor

noun
ag·​gres·​sor ə-ˈgres-ər How to pronounce aggressor (audio)
: a person or country that attacks without reasonable cause

Medical Definition

aggressor

noun
ag·​gres·​sor ə-ˈgres-ər How to pronounce aggressor (audio)
: one who exhibits aggression

More from Merriam-Webster on aggressor

Nglish: Translation of aggressor for Spanish Speakers

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