aggression

American  

[uh-gresh-uhn] / əˈgrɛʃ ən /

noun

1. the action of a state in violating by force the rights of another state, particularly its territorial rights; an unprovoked offensive, attack, invasion, or the like.

   The army is prepared to stop any foreign aggression.

   Antonyms:

   peacefulness

2. any offensive action, attack, or procedure; an inroad or encroachment.

   an aggression upon one's rights.

3. the practice of making assaults or attacks; offensive action in general.

4. Psychiatry. overt or suppressed hostility, either innate or resulting from continued frustration and directed outward or against oneself.

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aggression British  

/ əˈɡrɛsə, əˈɡrɛʃən /

noun

1. an attack or harmful action, esp an unprovoked attack by one country against another

2. any offensive activity, practice, etc

   an aggression against personal liberty

3. psychol a hostile or destructive mental attitude or behaviour

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aggression Scientific  

/ ə-grĕsh′ən /

1. Behavior that is meant to intimidate or injure an animal of the same species or of a competing species but is not predatory. Aggression may be displayed during mating rituals or to defend territory, as by the erection of fins by fish and feathers by birds.

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Other Word Forms

• aggressor
  noun
• antiaggression
  adjective
• counteraggression
  noun
• preaggression
  noun

Etymology

Origin of aggression

1605–15; < Latin aggressiōn- (stem of aggressiō ), equivalent to aggress ( us ) ( see aggress) + -iōn- -ion

Explanation

Aggression is hostile, purposely unfriendly behavior that can sometimes be violent. A motorist who shows aggression for another may follow too closely, honk the horn, or otherwise try to intimidate. When someone deliberately tries to make another person feel intimidated or threatened, it's an act of aggression. Forceful, unfriendly behavior towards others is one example of aggression, and one country's hostile action toward another is also a kind of aggression. It's been used since the 1600s to mean "an unprovoked attack," from the Latin root word aggressionem, "attack," and in 1912 aggression was first used to mean generally "hostile behavior."

Example Sentences

Beyond its enormous size, researchers believe Tylosaurus rex was built for strength and aggression.

From Science Daily • May 23, 2026

For these and many other reasons, it is difficult to estimate precisely the Iran war’s net effect on the risks of opportunistic Chinese aggression against Taiwan.

From The Wall Street Journal • May 21, 2026

The war’s effects on opportunistic aggression are indeterminate at best.

From The Wall Street Journal • May 21, 2026

These latest interceptions come amid increased Russian aggression in the region, the MoD added, pointing to recent submarine activity over critical underwater British infrastructure in the North Sea.

From BBC • May 20, 2026

This restrains male aggression and enables humans selectively to control the herd’s procreation.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

Related Words

• assault
• encroachment
• invasion
• offensive
• onslaught
• raid