Answer: ringcycle

AnswerCrossword Clue
RINGCYCLEWagner work
RINGCYCLEMusical work in four parts, with its first part opening the Met's 2010-11 season
RINGCYCLEIt was parodied in Looney Tunes' "What's Opera, Doc?"
RINGCYCLEWagner opus