aggressor

noun

ag·​gres·​sor ə-ˈgre-sər 

: one that commits or practices aggression

Synonyms

• invader
• raider
• attacker

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

Some potential aggressors, like North Korea, will hint at violence but stop short of openly declaring an intent to strike. —Big Think, 20 Oct. 2025

After the main event, Bron Breakker and Bronson Reed brutally attacked their leader, with Paul Heyman aligning with the two aggressors. —Andrew Ravens‎, MSNBC Newsweek, 17 Oct. 2025

Defense Secretary Pete Hegseth, in remarks at a NATO gathering this week, also ramped up rhetoric against Russia, notably calling Moscow the aggressor. —Alexandra Hutzler, ABC News, 17 Oct. 2025

The offensive line, which was a major question mark coming into the season, was the aggressor all night and kept the Wolverines on their heels. —The Athletic College Football Staff, New York Times, 12 Oct. 2025

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

Rhymes for aggressor

• assessor
• compressor
• confessor
• depressor
• hairdresser
• necessar
• oppressor
• possessor
• processor
• professor
• repressor
• successor

Kids Definition

aggressor

noun

ag·​gres·​sor ə-ˈgres-ər 

: a person or country that attacks without reasonable cause

Medical Definition

aggressor

noun

ag·​gres·​sor ə-ˈgres-ər 

: one who exhibits aggression