Bariatrician: A physician practicing bariatrics, the field of medicine concerned with weight loss. Also called a bariatric physician. The terms are used interchangeably. The American Society of Bariatric Physicians states that: 'These guidelines provide suggestions for the work-up and follow-up of the bariatric patient. They are not intended to rep... Found on http://www.medterms.com/script/main/art.asp?articlekey=32542