1.nounA totalitarian leader of a country, nation, or government.
"Dictators are always punished eventually."
2.nounA magistrate without colleague in republican Ancient Rome, who held full executive authority for a term granted by the senate (legislature), typically to conduct a war.
3.nounA tyrannical boss or authority figure.
4.nounA person who dictates text (e.g. letters to a clerk).