What's a Fascist?

My 15 yr. old son asked me the other day, when I'm trying to describe what ANTIFA  (Anti-Fascist) means....  "Mom, what exactly IS a "Fascist?"

Well son... where to start?  From wordhippo.com: 

fascism

Noun

1. (historical) A political regime, having totalitarian aspirations, ideologically based on a relationship between business and the centralized government, business-and-government control of the marketplace, repression of criticism or opposition, a leader cult and exalting the state and/or religion above individual rights.
2. (by extension) Any system of strong autocracy or oligarchy usually to the extent of bending and breaking the law, race-baiting and violence against largely unarmed populations.

And the OPPOSITE of Fascism is: 

"Opposite of an authoritarian and nationalistic right-wing system of government and social organization, of a government in which a single ruler (a tyrant) has absolute power, or Opposite of prolonged cruel or unjust treatment, especially through the exercise of authority."