of or pertaining to a governmental or political system, principle, or practice in which individual freedom is held as completely subordinate to the power or authority of the state, centered either in one person or a small group that is not constitutionally accountable to the people.
exercising complete or almost complete control over the will of another or of others:
an authoritarian parent.
a person who favors or acts according to authoritarian principles.
1862, "favoring imposed order over freedom," from authority + -an. Cf. authoritative, which originally had this meaning to itself. Noun in the sense of one advocating or practicing such governance is from 1859.