ag·​gres·​sor | \ə-ˈgre-sər \

Definition of aggressor 

: one that commits or practices aggression

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Synonyms for aggressor


invader, raider

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Examples of aggressor in a Sentence

Each country accused the other of being the aggressor. these pocket-size states had formed an alliance to deter potential aggressors

Recent Examples on the Web

Gianforte initially told police that Jacobs attacked him first, and his campaign initially released a statement repeating that Jacobs was the aggressor. Matt Volz, The Seattle Times, "Reporter warns Rep. Gianforte not to lie about 2017 attack," 26 Oct. 2018 About a month ago at a bar, a woman lambasted her for staking out more than her fair share of real estate, then recruited the bartender for backup, who agreed that Finck was the aggressor. Julia Felsenthal, Vogue, "In a New Graphic Memoir, Liana Finck Traces Her Own Origin Story," 18 Sep. 2018 Despite Morocco having failed to capitalise on their ascendancy despite being the aggressor in the Group B match-up, the Portuguese manager admitted his side's performance spelt trouble., "Portugal Boss 'Not Happy' With 'Out of Control' Performance in Narrow Win Over Morocco," 20 June 2018 The Cavs came in wanting to play faster and be more physical with the younger Celtics, who were the aggressors in Games 1 and 2. Tom Withers,, "On time, on target: LeBron James and Cavaliers pound Celtics in Game 3," 20 May 2018 Police could not determine a primary aggressor and cited both women for disorderly conduct. Jeff Piorkowski/special To,, "Drunk man found asleep at the wheel, his car on tree lawn: Cleveland Heights police blotter," 9 Mar. 2018 The third time, Malkin retaliated, which sent both him and his aggressor, Brandon Manning, to the penalty box for roughing. Marcus Hayes,, "Flyers, inspired by Sean Couturier, come of age in Game 5 win over Penguins | Marcus Hayes," 20 Apr. 2018 Police eventually determined Ragin was the primary aggressor. Campbell Lutz, ajc, "NFL veteran ‘Pacman’ Jones assaulted at Atlanta airport, police say," 12 July 2018 Police determined that the mother was the primary aggressor. Jeff Piorkowski/special To,, "Two mothers charged in domestic violence incidents involving their grown daughters: University Heights police blotter," 8 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aggressor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of aggressor

1585, in the meaning defined above

History and Etymology for aggressor

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

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Statistics for aggressor

Last Updated

15 Nov 2018

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Time Traveler for aggressor

The first known use of aggressor was in 1585

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More Definitions for aggressor



English Language Learners Definition of aggressor

: a person or country that attacks another : a person or country that starts a fight or war


ag·​gres·​sor | \ə-ˈgre-sər \

Kids Definition of aggressor

: a person or a country that engages in hostile action without reasonable cause


ag·​gres·​sor | \ə-ˈgres-ər \

Medical Definition of aggressor 

: one who exhibits aggression

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Comments on aggressor

What made you want to look up aggressor? Please tell us where you read or heard it (including the quote, if possible).


something that serves to warn or remind

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