tyrannical

adjectives

marked by unjust severity or arbitrary behavior
"the oppressive government"; "oppressive laws"; "a tyrannical parent"; "tyrannous disregard of human rights"
is derived from
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"
is derived from