TYRANNIC

authoritarian, autocratic, dictatorial, despotic, tyrannic, tyrannical

(adjective) 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”

Source: WordNet® 3.1

Adjective

tyrannic (comparative more tyrannic, superlative most tyrannic)

(dated) Tyrannical.

Source: Wiktionary

Ty*ran"nic, Ty*ran"nic*al, a. Etym: [L. tyrannicus, Gr. tyrannique. See Tyrant.]

Definition: Of or pertaining to a tyrant; suiting a tyrant; unjustly severe in government; absolute; imperious; despotic; cruel; arbitrary; as, a tyrannical prince; a tyrannical master; tyrannical government. "A power tyrannical." Shak. Our sects a more tyrannic power assume. Roscommon. The oppressor ruled tyrannic where he durst. Pope.

– Ty*ran"nic*al*ly, adv.

– Ty*ran"nic*al*ness, .

Source: Webster’s Unabridged Dictionary 1913 Edition