1. A severe psychiatric disorder with symptoms of emotional instability, detachment from reality, often with delusions and hallucinations, and withdrawal into the self.
2. The term schizophrenia was introduced in 1911 by Eugen Bleuler because neither early onset nor terminal deterioration is an essential feature of the mental disease. Bleuler described the schizophrenias as a slowly progressive deterioration of the entire personality, which involves mainly the affective life, and expresses itself in disorder of feeling, thought and conduct, and a tendency to withdraw from reality.
3. A mental disorder occurring in various forms, all characterized by a breakdown in the relation between thoughts, feelings, and actions; usually with a withdrawal from social activities and the occurrence of delusions and hallucinations.
4. An offensive term for contradictory or conflicting attitudes, behavior, or qualities.

A form of any of several psychotic disorders characterized by distortions of reality, usually of the simple but also additional symptoms of mood disorders: The person so afflicted with ambulatory schizophrenia usually manages for the most part to avoid being institutionalized.

A form of schizophrenia characterized by a persistent preoccupation with illogical, absurd, and changeable delusions; usually, of a persecutory, grandiose, or jealous nature, accompanied by related hallucinations.

The symptoms include extreme anxiety, exaggerated suspiciousness, aggressiveness, anger, argumentativeness, and hostility, which may lead to violence.