AGGRESSION
aggression, hostility
(noun) violent action that is hostile and usually unprovoked
aggression
(noun) deliberately unfriendly behavior
aggression
(noun) the act of initiating hostilities
aggression
(noun) a disposition to behave aggressively
aggression, aggressiveness
(noun) a feeling of hostility that arouses thoughts of attack
Source: WordNet® 3.1
Etymology
Noun
aggression (countable and uncountable, plural aggressions)
The act of initiating hostilities or invasion.
The practice or habit of launching attacks.
Hostile or destructive behavior or actions.
Antonyms
• nonaggression
Source: Wiktionary
Ag*gres"sion, n. [L. aggressio, fr. aggredi: cf. F. agression.]
Definition: 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
Syn. -- Attack; offense; intrusion; provocation.
Source: Webster’s Unabridged Dictionary 1913 Edition