# aggressor

/əˈɡɹɛsɝ/ (US) · /ɐɡɹˈɛsɐ/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/aggressor
Updated: 2026-05-11

## Definition

a person, group, or country that starts a fight or an attack without being provoked first.

For teachers: a person or entity that initiates a hostile action or an unprovoked attack. Often used in legal or political contexts to distinguish the initiator from the party acting in self-defence.

## Examples

- The international community identified the neighbouring country as the aggressor.
- In many legal systems, the court must determine who was the initial aggressor before deciding if a claim of self-defence is valid.
- Historians continue to debate whether the empire was a calculated aggressor seeking expansion or merely a reactive power responding to perceived threats on its borders.

## Usage notes

- Commonly used in the singular to identify a specific party in a conflict.

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