tyranny

(noun) a form of government in which the ruler is an absolute dictator (not restricted by a constitution or laws or opposition etc.). Synonyms: dictatorship, absolutism, authoritarianism, Caesarism, despotism, monocracy, one-man rule, shogunate, Stalinism, totalitarianism.

(noun) dominance through threat of punishment and violence. Synonyms: absolutism, despotism.