WordReference Random House Unabridged Dictionary of American English © 2026
ag•gres•sor
(ə gres′ər),USA pronunciation n.
- a person, group, or nation that attacks first or initiates hostilities;
an assailant or invader.
- Late Latin, Latin aggred- (stem of aggredī to attack; see aggress) + -tor -tor
- 1670–80
'aggressor' also found in these entries (note: many are not synonyms or translations):