The Collaborative International Dictionary of English v.0.48:

Bacchanalian \Bac`cha*na"li*an\ (b[a^]k`k[.a]*n[=a]"l[i^]*an;
   106), a.
   Of or pertaining to the festival of Bacchus; relating to or
   given to reveling and drunkenness.
   [1913 Webster]

         Even bacchanalian madness has its charms. --Cowper.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bacchanalian \Bac`cha*na"li*an\, n.
   A bacchanal; a drunken reveler.
   [1913 Webster]

WordNet (r) 3.0 (2006):

bacchanalian
    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]