Yours, Etc.: Origins and Uses of 8 Sign-Offs
psychosis psy·cho·sis (sī-kō'sĭs)
n. pl. psy·cho·ses (-sēz)
A severe mental disorder, with or without organic damage, characterized by derangement of personality and loss of contact with reality and causing deterioration of normal social functioning.
Plural psychoses (sī-kō'sēz)
A mental state caused by psychiatric or organic illness, characterized by a loss of contact with reality and an inability to think rationally. A psychotic person often behaves inappropriately and is incapable of normal social functioning.
psychotic adjective (sī-kŏt'ĭk)
A severe mental disorder, more serious than neurosis, characterized by disorganized thought processes, disorientation in time and space, hallucinations, and delusions. Paranoia, manic depression, megalomania, and schizophrenia are all psychoses. One who suffers from psychosis is psychotic.