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.
This time, though, the United States appeared to favor the aggressor, not the victim. — Doyle McManus, Los Angeles Times, 26 Oct. 2026 According to Gatto, the right traditionally emphasizes tougher criminal penalties for aggressors, while the left places greater emphasis on protection and support for victims, including shelters and specialized services. — Alessandra Freitas, CNN Money, 25 Oct. 2026 This was wrong, Walzer insisted—such a principle would encourage aggressors to be as destructive as possible. — Jordi Graupera, New Yorker, 22 Oct. 2026 The negotiation track has support from Ukraine but none so far from the aggressor, Russia. — David Ignatius, Washington Post, 21 Oct. 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 1 Nov. 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
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