Psychiatrist

n. medical doctor who specializes in the diagnosis and treatment of mental illnesses

A psychiatrist is a physician who specializes in psychiatry and is certified in treating mental illness. As part of their evaluation of the patient, psychiatrists are one of only a few mental health professionals who may prescribe psychiatric medication, conduct physical examinations, order and interpret laboratory tests and electroencephalograms, and may order brain imaging studies such as computed tomography or computed axial tomography, magnetic resonance imaging, and positron emission tomography scanning.
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Noun
1. a physician who specializes in psychiatry
(synonym) head-shrinker, shrink
(hypernym) specialist, medical specialist
(hyponym) alienist

A physician specializing in the prevention, diagnosis, and treatment of mental illness.

A psychiatrist is a professional who completed both medical school and training in psychiatry and is a specialist in diagnosing and treating mental illness.