a ruler with unlimited powers; a cruel and unjust ruler;
a dictator; a despot; a tyrant, an authoritarian;
a person, usually a businessperson, who expects and orders others to do things without showing their feelings or wishes,
Some of our countrymen believe that our President is an autocrat.
Some political pundits feel that most of the Russian Tsars were autocrats.
A corporate autocrat is the one who has complete control over a specific business and behaves ruthlessly in his/her business dealings.