a form of government in which the ruler is an absolute dictator (not restricted by a constitution or laws or opposition etc.)

Despotism is a form of government by a single authority, either an individual or tightly knit group, which rules with absolute political power. In its classical form, a despotism is a state where one single man, called a Despot, wields all the power and authority, and everyone else is considered his slave. This form of despotism was the first known form of statehood and civilization; the Pharaoh of Egypt is a hallmark of a classical Despot.