Aggression is defined as an unprovoked attack or harmful action against another.(noun)
An example of an aggression is a dog barking and chasing after another dog in an effort to attack.
The definition of aggression refers to the practice of being offensive or prone to attacking others.(noun)
An example of someone who is prone to bouts of aggression would be someone who is routinely starting fights.
See aggression in Webster's New World College Dictionary
Origin: Fr < L aggressio: see aggress
See aggression in American Heritage Dictionary 4
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