autocratic, bossy, dominating, high-and-mighty, magisterial, peremptory -- (offensively self-assured or given to exercising usually unwarranted power; "an autocratic person"; "autocratic behavior"; "a bossy way of ordering others around"; "a rather aggressive and dominating character"; "managed the employees in an aloof magisterial way"; "a swaggering peremptory manner")
authoritarian, autocratic, dictatorial, despotic, tyrannic, tyrannical -- (characteristic 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")