However, aggressive can mean a people who is hard-working to achieve success. It can also mean that a people who wants to have a higher rank always do things which satisfy people.
In Oxford, it means ready or likely to attack or confront; characterized by or resulting from aggression and behaving or done in a determined and forceful way.
In Wikipedia, in psychology, as well as other social and behavioral sciences, aggression refers to behavior between members of the same species that is intended to cause humiliation, pain, or harm.
In Wiktionary, it means tending or disposed to aggress; characterized by aggression; making assaults; unjustly attacking.
Aggressive is an expression or emotion. The color is not exaggerated and it seems colorless in aggressive. The color is just bringing the mood to aggressive. Hence, it is categorized as imaginary color.