What does aggress mean?
To aggress is to launch an attack or initiate hostilities against someone or something. The word is the verbal root of the far more familiar nouns 'aggression' and 'aggressor', yet it survives only marginally in modern English, appearing chiefly in formal legal, diplomatic, and academic contexts — for example, in discussions of whether one state has aggressed against another. It is normally intransitive and often paired with 'against': 'a power that aggresses against its neighbours'. Because everyday English prefers 'attack', 'assault', or simply the adjective 'aggressive', encountering 'aggress' can feel slightly archaic or bureaucratic. Its value lies precisely in that formality: it names the act of being the instigator of hostility, without specifying weapons, scale, or outcome, which makes it useful in treaties, tribunals, and scholarly prose where precision about who struck first matters more than vivid description.
verbTo make an attack or begin hostilities against someone or something; to act aggressively toward another party.
- To initiate an attack or hostilities against a person, group, or nation.
"The tribunal ruled that one nation had aggressed against its neighbour without provocation."
"Under international law, a state that aggresses against another forfeits certain protections."
"The report documented how the regime had repeatedly aggressed upon its own citizens."
You know the words 'aggressive' and 'aggression' by heart — but their parent verb 'aggress' is so rare that most native English speakers have never once used it.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of aggress
Aggress derives from Latin aggredi 'to approach, attack', formed from ad- ('toward') plus gradi ('to step, walk'), the same verb that gives English 'progress', 'digress', 'egress', and 'transgress'. The word entered English in the early seventeenth century, borrowed either directly from Latin or through its French descendant agresser. Its derivative 'aggression' became firmly established in international law in the twentieth century, while the parent verb remained comparatively rare.
Related word forms
How aggress is actually used
Aggress is a formal, largely technical word found mainly in legal and international-relations writing; in everyday speech people use 'attack', 'assault', or adjectives like 'aggressive' instead. It is typically used intransitively ('to aggress against someone'), and the phrase 'aggress against' is more common than the bare verb.
Easily confused with aggress
Aggression is the noun referring to hostile or violent behaviour itself, while aggress is the rarer verb describing the act of initiating such an attack.