What is an osteopathic psychiatrist?

There's technically no such thing as an "osteopathic psychiatrist", but what you might be referring to is an osteopathic physician who has earned the Doctor of Osteopathic Medicine degree (D.O.) who specializes in psychiatry and practices as a psychiatrist. A psychiatrist with a D.O. after their name is still a psychiatrist who treats patients for emotional problems or mental illness and still went through four years of medical school and residency.