or Dionysia
In Greco-Roman religion, any of the festivals of the wine god Bacchus ( Dionysus ), which probably originated as fertility rites.
The most famous Greek festivals included the Greater Dionysia, with its dramatic performances; the Anthesteria ; and the Lesser Dionysia, characterized by simple rites. Bacchanalia were introduced from lower Italy into Rome, where they were at first secret, open only to women, and held three times a year. They later admitted men and became as frequent as five times a month. In 186 BC their reputation as orgies led the Senate to prohibit them throughout Italy, except in special cases.