archtyrant
/ˈɑːrtɪrænt/Definitions
1. noun
A ruler who exercises absolute authority and power
“The archtyrant’s regime lasted for decades, marked by brutal suppression of dissent.”
2. noun
A person who is tyrannical in their attitude or behavior, especially in a particular sphere of activity or situation
“The company’s CEO was seen as an archtyrant by his employees, who felt he micromanaged every aspect of their work.”