: a psychosis characterized by systematized delusions of persecution or grandeur usually without hallucinations
: a tendency on the part of an individual or group toward excessive or irrational suspiciousness and distrustfulness of others
Mental disorder characterized by delusions of persecution or grandeur, usually without hallucinations. Paranoia was formerly classified as a distinct psychosis but is now generally treated as one of several varieties of schizophrenia or, in milder cases, of personality disorder. The paranoid person generally suffers from exaggerated self-reference, a tendency to construe independent events and acts as pertaining to him- or herself.