Amygdala refers to an area in the core of the brain and part of the limbic system of the brain located deep in the temporal lobe that is associated with aggressive behaviors.
Damage causes changes in emotional and aggressive behaviour
Other /More definition:
Amygdala is a part of the limbic system (within the brain) associated with fear responses; an area of brain tissue with extensive connections to the olfactory system and hypothalamus, thought to be involved in mood, feeling, instinct, and short-term memory.
Amygdala is literally refers to "almond," because of its shape has a specific role in fear conditioning and impacts the strength of stored memory; it plays an important role in emotion, especially in anger and aggression
Moreover, it is a subcortical structure that is involved in emotional responding and in processing olfactory signals.