[syn: authoritarian, autocratic, dictatorial, despotic, tyrannic, tyrannical]
The Collaborative International Dictionary of English v.0.48:
Dictatorial \Dic`ta*to"ri*al\, a. [Cf. F. dictatorial.]
   1. Pertaining or suited to a dictator; absolute.
      [1913 Webster]
            Military powers quite dictatorial.    --W. Irving.
      [1913 Webster]
   2. Characteristic of a dictator; imperious; dogmatical;
      overbearing; as, a dictatorial tone or manner. --
      Dic`ta*to"ri*al*ly, adv. -- Dic`ta*to"ri*al*ness, n.
      [1913 Webster]
WordNet (r) 3.0 (2006):
dictatorial
    adj 1: of or characteristic of a dictator; "dictatorial powers"
    2: expecting unquestioning obedience; "the timid child of
       authoritarian parents"; "insufferably overbearing behavior
       toward the waiter" [syn: authoritarian, dictatorial,
       overbearing]
    3: 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" [syn: authoritarian, autocratic,
       dictatorial, despotic, tyrannic, tyrannical]
Moby Thesaurus II by Grady Ward, 1.0:
71 Moby Thesaurus words for "dictatorial":
   U, absolute, absolutist, absolutistic, all-powerful, arbitrary,
   aristocratic, arrogant, authoritarian, authoritative, autocratic,
   autonomous, bossy, bureaucratic, civic, civil, constitutional,
   democratic, despotic, domineering, elitist, fascist, federal,
   federalist, federalistic, feudal, governmental, grinding,
   gubernatorial, heteronomous, high and mighty, high-handed,
   hubristic, imperative, imperial, imperious, lordly, magisterial,
   magistral, masterful, matriarchal, matriarchic, monarchal,
   monarchial, monarchic, monocratic, official, oligarchal,
   oligarchic, omnipotent, oppressive, overbearing, overruling,
   parliamentarian, parliamentary, patriarchal, patriarchic,
   peremptory, pluralistic, political, repressive, republican,
   self-governing, severe, strict, suppressive, theocratic,
   totalitarian, tyrannical, tyrannous, unlimited