Psychiatry (noun)

The branch of medicine concerned with the study, treatment, and prevention of mental illness.

Origin:

Mid 19th century: via german from french psychiatrie, from greek psykhe "soul" + iatrikē "healing", from iatros "healer".

Examples:

1. He is a specialist in psychiatry.
2. She is a psychiatrist and studies mental health.
3. He is a patient in a psychiatry clinic.
4. Psychiatry is the branch of medicine that deals with mental illness.
5. The hospital has a large department of psychiatry.