authoritarian

(noun) a person who behaves in a tyrannical manner. Synonyms: dictator. Example: "My boss is a dictator who makes everyone work overtime."

(adj) characteristic of an absolute ruler or absolute rule; having absolute sovereignty. Synonyms: autocratic, dictatorial, despotic, tyrannic, tyrannical. Examples: "An authoritarian regime." "Autocratic government." "Despotic rulers." "A dictatorial rule that lasted for the duration of the war." "A tyrannical government."

(adj) expecting unquestioning obedience. Synonyms: dictatorial, overbearing. Examples: "The timid child of authoritarian parents." "Insufferably overbearing behavior toward the waiter."