The Collaborative International Dictionary of English v.0.48:

Bacchic \Bac"chic\, Bacchical \Bac"chic*al\, a. [L. Bacchicus,
   Gr. Bakchiko`s.]
   Of or relating to Bacchus; hence, jovial, or riotous, with
   intoxication; riotously drunken; -- used of revelrous
   gatherings.

   Syn: bacchanalian, bacchanal, bibulous, carousing,
        drunken(prenominal), orgiastic, riotous
        [1913 Webster + WordNet 1.5]

WordNet (r) 3.0 (2006):

bacchic
    adj 1: used of riotously drunken merrymaking; "a night of
           bacchanalian revelry"; "carousing bands of drunken
           soldiers"; "orgiastic festivity" [syn: bacchanalian,
           bacchanal, bacchic, carousing, orgiastic]

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "bacchic":
   Dionysiac, amok, berserk, corybantic, desperate, frantic, frenetic,
   frenzied, furious, like one possessed, mad, madding, maenadic,
   maniac, maniacal, rabid, raging, ranting, raving, raving mad,
   running wild, stark-raving mad, uncontrollable, violent, wild