aggressor

noun

ag·​gres·​sor ə-ˈgre-sər 

: one that commits or practices aggression

Synonyms of aggressor

• 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

Phillips’ attorney, Ivan Rodriguez, has sharply disputed the prosecution’s version of events, telling KTVU that his client was not the aggressor and that video evidence shows the officer initiated physical contact. —Stepheny Price, FOXNews.com, 18 Mar. 2026

Most people initially become aware of the reptiles by hearing their rattles, which the snakes use to try to scare off aggressors or to distract prey. —Gary Robbins, San Diego Union-Tribune, 18 Mar. 2026

Her journey towards long-lasting sobriety aligns with her unfolding detective work to find her anonymous aggressor. —Courtney Howard, Variety, 15 Mar. 2026

The attack on the oil depots could be construed as chemical warfare, which violates international law, because the aggressors likely knew the hazards the civilians who live in Tehran would face, Cleetus said. —Julia Jacobo, ABC News, 10 Mar. 2026

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