The Collaborative International Dictionary of English v.0.48:

Pretorian \Pre*to"ri*an\, a. [L. praetorians: cf. F.
   pr['e]torien.]
   Of or pertaining to a pretor or magistrate; judicial;
   exercised by, or belonging to, a pretor; as, pretorian power
   or authority.
   [1913 Webster]

   Pretorian bands or Pretorian guards, or Pretorians
      (Rom. Hist.), the emperor's bodyguards, instituted by the
      Emperor Augustus in nine cohorts of 1,000 men each.

   Pretorian gate (Rom. Antiq.), that one of the four gates in
      a camp which lay next the enemy. --Brande & C.
      [1913 Webster]