In medicine, a surgeon is a specialist in surgery. Surgery is a broad category of invasive medical treatment that involves the cutting of a body, whether that of a human or other animal, for a specific reason such as the removal of diseased tissue or to repair a tear or breakage.
In the U.S., surgeons train for longer than other specialists; only after 9 years of training do they qualify. These years include 4 years of medical school and a minimum of 5 years of residency.