Canadian electronic DJ Deadmau5 has entered into a high-profile feud with Madonna, calling the Material Girl an "idiot" after she appeared to glamorize drug use during a recent concert.

The 53-year-old pop star was performing at the Ultra Music Festival in Miami over the weekend when she asked the crowd: "How many people in this crowd have seen Molly?"

Molly is a slang term for MDMA, otherwise known as the drug ecstasy.

The crowd cheered in response -- the incident has been documented on YouTube — but Deadmau5 was less enthusiastic.

The DJ from Niagara Falls, Ont., took to Facebook to slam Madonna with an expletive-filled rant condemning her behaviour.

"Very classy there Madonna. 'HUR DUR HAS ANYONE SEEN MOLLY???"' wrote the four-time Juno winner, whose real name is Joel Zimmerman, on Monday.

"Such a great message for the young music lovers at Ultra. Quite the…philanthropist. But hey, at least (you're) HIP AND TRENDY!…That's your big message to Ultra attendees? Hipsterspeak for looking for drugs?"

He then spent much of the morning arguing with dozens of Madonna's fans via Twitter, while reiterating his point with the level of vitriol toned down.

"At the end of the day, it's a slap in the face associating a potentially harmful substance to the work and passion we put in to make art," he wrote.

There has so far been no response from Madonna.