1. A person with a mental disorder characterized by an extremely antisocial personality that often leads to aggressive, perverted, or criminal behavior. • The formal psychiatric term for the mental illness from which a psychopath suffers is antisocial personality disorder.
2. Loosely, a person who is mentally ill or unstable. — Also termed sociopath. [Cases: Mental Health
3. C.J.S. Insane Persons§§ 2, 6.] — psychopathy (sI-kop-[schwa]-thee), n. — psychopathic (sI-k[schwa]-path-ik), adj.