Wild parties (9)
'wild parties' is the definition.
(orgy can mean a wild or drunken party)
This is all the clue.
(Other definitions for orgies that I've seen before include "Wild licentious parties" , "Wild parties with excessive drinking and sexual activity" , "Acts of immoderate indulgence" , "Drunken revels" .)
(Other definitions for revelries that I've seen before include "Fantasies" , "Lively festivities" .)