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Related to functional psychosis: organic psychosis, schizophrenia
an obsolete term once used to denote schizophrenia and other severe mental disorders before modern science discovered a biological component to some aspects of each of the disorders.
a severe emotional disorder characterized by personality derangement and loss of ability to function in reality, but without evidence that the disorder is related to the physical processes of the brain.
func·tion·al psy·cho·sis(fungkshŭn-ăl sī-kōsis)
Mental disorder that does not have a verifiable physical cause.
A psychosis in which there is no apparent pathology of the central nervous system.
See also: psychosis