Psychiatry is the medical specialty devoted to the diagnosis, prevention and treatment of mental disorders. These include various maladaptations related to mood, behaviour, cognition, and perceptions. See glossary of psychiatry.
Mental illness is a myth. Psychiatrists are not concerned with mental illnesses and their treatments. In actual practice they deal with personal, social and ethical problems in living.
Thomas Szasz, The Myth of Mental Illness: Foundations of a Theory of Personal Conduct (1974)