The first attack, or act of hostility; the first act of injury, or first act leading to a war or a controversy; unprovoked attack; assault; as, a war of aggression. “Aggressions of power.” Hallam [1913 Webster]

Syn. -- Attack; offense; intrusion; provocation.

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OXFORD DICTIONARY

aggression, n.
1 the act or practice of attacking without provocation, esp. beginning a quarrel or war.
2 an unprovoked attack.
3 self-assertiveness; forcefulness.
4 Psychol. hostile or destructive tendency or behaviour.

Etymology

F agression or L aggressio attack f. aggredi aggress- (as AD-, gradi walk)

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THESAURUS

aggression

adventuresomeness, adventurousness, aggravated assault, aggressiveness, ambitiousness, amphibious attack, antagonism, armed assault, assailing, assailment, assault, attack, banzai attack, bellicism, bellicosity, belligerence, belligerency, blitz, blitzkrieg, breakthrough, charge, chauvinism, combativeness, contentiousness, counterattack, counteroffensive, coup de main, crippling attack, dead set at, descent on, diversion, diversionary attack, drive, dynamism, encroachment, enterprise, enterprisingness, ferocity, fierceness, fight, flank attack, force, forcefulness, frontal attack, gas attack, get-up-and-get, get-up-and-go, getup, go, go-ahead, go-getting, go-to-itiveness, gumption, head-on attack, hostility, hustle, incursion, infiltration, initiative, inroad, invasion, irruption, jingoism, lightning attack, lightning war, martialism, mass attack, megadeath, militancy, militarism, mugging, offense, offensive, onset, onslaught, overkill, panzer warfare, pugnaciousness, pugnacity, push, pushfulness, pushiness, pushingness, quarrelsomeness, raid, run against, run at, rush, saber rattling, sally, shock tactics, sortie, spirit, spunk, strike, truculence, unfriendliness, unpeacefulness, unprovoked assault, up-and-comingness, venturesomeness, venturousness, warmongering, warpath

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ROGET THESAURUS

aggression

Attack

N attack, assault, assault and battery, onset, onslaught, charge, aggression, offense, incursion, inroad, invasion, irruption, outbreak, estrapade, ruade, coupe de main, sally, sortie, camisade, raid, foray, run at, run against, dead set at, storm, storming, boarding, escalade, siege, investment, obsession, bombardment, cannonade, fire, volley, platoon fire, file fire, fusillade, sharpshooting, broadside, raking fire, cross fire, volley of grapeshot, whiff of the grape, feu d'enfer, cut, thrust, lunge, pass, passado, carte and tierce, home thrust, coupe de bec, kick, punch, battue, razzia, Jacquerie, dragonnade, devastation, eboulement, assailant, aggressor, invader, base of operations, point of attack, echelon, attacking, aggressive, offensive, obsidional, up in arms, on the offensive, Int, up and at them!, the din of arms, the yell of savage rage, the shriek of agony, the groan of death, their fatal hands no second stroke intend, thirst for glory quells the love of life.

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