Bariatric is a confusing word, I defined it earlier but people mishear or get it wrong. What its not
Balearic surgery - presumably something to do with Ibiza
Barometric Surgery - Something to do with air pressure -(thanks to Paul Hackett)
Barbaric surgery -said the spell checker, have you seen the video.
Hyperbaric surgery - the surgeon wears a divers suit
Geriatric surgery - presumably when they remove an old person from your stomach.