orgy

1. (originally) A secret rite or ceremony, typically involving riotous and dissolute behavior, including dancing, drunkenness and indiscriminate sexual activity, undertaken in honor of various pagan gods or goddesses (such as Attis, Bacchus, Ceres, Dionysus, Osiris, etc). [from 16th c.]Examples: "Human sacrifices of a definitely black magical order took place at the tomb of Osiris, while similar orgies with human victims were performed at Heliopolis."