Open English Wordnet
Nouns
(n)authoritarian, dictatora person who behaves in a tyrannical manner“my boss is a dictator who makes everyone work overtime”
Adjectives
(s)authoritarian, autocratic, dictatorial, despotic, tyrannic, tyrannicalcharacteristic of an absolute ruler or absolute rule; having absolute sovereignty“an authoritarian regime”, “autocratic government”, “despotic rulers”, “a dictatorial rule that lasted for the duration of the war”, “a tyrannical government”
(s)authoritarian, dictatorial, overbearingexpecting unquestioning obedience“the timid child of authoritarian parents”, “insufferably overbearing behavior toward the waiter”