Malicious, violent, cruel, or harmful behavior. Aggression can manifest in physical actions, such as physical violence towards others, or in a more emotional way, such as cruel words or unkind behavior. Aggression can build up in an individual over time, due to anger, stress, or any negative circumstances. Acts of aggression are sometimes directed at the thing or individual which created the negative situation (attacking someone who is bullying you), but can also be directed at an innocent individual (saying something mean to your spouse after a bad day at work).
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