Orgy (noun)

1. A wild party, typically involving excessive drinking and promiscuous sexual activity.
2. A group of people engaged in such activity.

Origin:

From latin orgia, from ancient greek ὄργια (orgia, "secret rites"), from ὄργιος (orgios, "secret, mysterious"), from ὄργανον (organon, "instrument, tool"), from ὀργάνω (orgánō, "i work, i ac.t")

Examples:

1. The students threw an orgy at the frat house.
2. The party turned into an orgy after everyone got drunk.
3. The orgy involved a lot of nudity and sexual activity.
4. The orgy was a secret event known only to a select few.
5. The orgy was not an appropriate event to bring children to.