The definition of insanity is having a serious mental illness or being extremely foolish.(noun)
See insanity in Webster's New World College Dictionary
noun pl. insanities
Origin: L insanitas < insanus
See insanity in American Heritage Dictionary 4
noun pl. in·san·i·ties
See insanity in Ologies
a violent form of mania; incurable insanity.
1. a congenital condition of low intelligence.
2. a form of temporary insanity. Cf. dementia.
behavior characteristic of insanity. See also order and disorder.
a mental patient.
one of various forms of schizophrenia characterized by stupor, sometimes alternating with excited behavior and mechanical, repetitive behavior, accompanied by muscular rigidity. —catatonic, n., adj.
a state of maniacal excitement characterized by restless behavior, confused speech, and sometimes hallucinations.
madness or insanity. Cf. amentia.
1. Obsolete, the doctrine of demoniac possession.
2. Archaic. demonomania. —demonian, n., adj.
Medicine. a monomania in which a person believes he is possessed of devils. Also called demonopathy.
Medicine, Obsolete, a state in which a person believes he is possessed by a devil or has been endowed with supernatural powers.
a disordered mental condition in which the sufferer is prone to hallucinations.
a form of insanity or dementia praecox that can appear at puberty, characterized by foolish behavior and deterioration of the mental faculties.
an acute mania.
1. periodic insanity, once thought to be caused by the phases of the moon.
2. any form of insanity. —lunatic, adj.
an abnormal tendency toward deep melancholy.
an abnormal fear of becoming insane.
an abnormal fear of madness.
1. Medicine. a form of mental illness characterized by the unreasonable conviction in the patient of his own greatness, goodness, power, or wealth.
2. an obsession with extravagant or grand actions. — megalomaniac, n., adj. —megalomaniacal, adj.
a condition of abnormal gloom or depression, often of an intensity to become a form of insanity. —melancholiac, n., adj. —melancholie, n., adj.
Obsolete, a person suffering from melancholia; a melancholiac.
a form of treatment for mental illness that involves placing the patient under the influence of a narcotic.
the process of correcting bodily or mental distortion.
a mental disorder characterized by behavior that stems from an elaborately constructed system of delusions of persecution and grandeur. —paranoiac, n. —paranoid, adj.
a state resembling paranoia.
any severe mental disorder or disease. —psychotic, n., adj.
a psychotic condition marked by erratic behavior, withdrawal from reality, and intellectual and emotional deterioration. Also called dementia praecox. —schizophrenic, n., adj.
a mild form of schizophrenia, characterized by withdrawal, inversion, etc. —schizothyme, n. —schizothymic, adj.
a mild mania.
a form of insanity or mental disorder in which the sufferer imagines that he is an animal. —zoanthropic, adj.
a form of hallucination in which the sufferer imagines he sees animals. Also called zooscopy.
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