THE GREEKS HAD A WORD FOR IT...

According to the dictionary... Well, a dictionary...

The word orgy has become connected in the minds of many with unrestrained sexual activity, but its origins are much less licentious... The Greek word, orgia, was used with reference to the secret rites practiced in the worship of various deities, such as Orpheus and Dionysus. 

The word in Greek did not denote sexual activity, although this was a part of some rites. The rites of Dionysus, for example, included only music, dancing, drinking, and the eating of animal sacrifices. Having passed through Latin and Old French into English, the word orgy is first recorded in English with reference to the secret rites of the Greek and Roman religions in 1589. It is interesting to note that the word is first recorded with its modern sense in 18th-century English and perhaps in 17th-century French. Whether this speaks to a greater licentiousness in society or not must be left to the historian, but certainly the religious nature of the word has gone into eclipse.

In fact, here in Greece, it's now something to do with an ICE CREAM!