From Longman Dictionary of Contemporary Englishtyrantty‧rant /ˈtaɪərənt $ ˈtaɪr-/ ●○○ noun [countable] 1 PGGOVERENMENTa ruler who has complete power and uses it in a cruel and unfair way The country had long been ruled by tyrants.2 CRUELsomeone who has power over other people, and uses it cruelly or unfairly My headmaster was a real tyrant.
Examples from the Corpus
tyrant• She was a tyrant who had absolutely no tolerance for mistakes.• Little Kyle is an absolute tyrant in the family.• Comparisons between twentieth-century dictators and the classical tyrants of Ancient Rome are alluring but misleading.• The Romanian tyrant Ceaucescu was overthrown in 1989.• Small children are encouraged to be small tyrants, to react violently if thwarted.• When the islanders knew themselves freed from the tyrant it was easy for Perseus to find Danae and Dictys.Origin tyrant (1200-1300) Old French tyran, tyrant, from Latin tyrannus, from Greek tyrannos 