Source : Webster's Revised Unabridged Dictionary (1913)

Saturnalia \Sat`ur*na"li*a\, n. pl. [L. See {Saturn}.]
   1. (Rom. Antiq.) The festival of Saturn, celebrated in
      December, originally during one day, but afterward during
      seven days, as a period of unrestrained license and
      merriment for all classes, extending even to the slaves.

   2. Hence: A period or occasion of general license, in which
      the passions or vices have riotous indulgence.

Source : WordNet®

Saturnalia
     n 1: an orgiastic festival in ancient Rome in honor of Saturn
     2: a wild gathering involving excessive drinking and
        promiscuity [syn: {orgy}, {debauch}, {debauchery}, {riot},
         {bacchanal}, {bacchanalia}, {drunken revelry}]