any of the various forms of psychosis or severe neurosis.
Words nearby mental illness
Origin of mental illness
First recorded in 1960–65
Also called mental disorder, mental disease.
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British Dictionary definitions for mental disorder (1 of 2)
law (in England, according to the Mental Health Act 1983) mental illness, arrested or incomplete development of mind, psychopathic disorder, or any other disorder or disability of the mind
Derived forms of mental disordermentally disordered, adjective
British Dictionary definitions for mental disorder (2 of 2)
any of various disorders in which a person's thoughts, emotions, or behaviour are so abnormal as to cause suffering to himself, herself, or other people
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medical definitions for mental disorder (1 of 2)
Medical definitions for mental disorder (2 of 2)
Any of various psychiatric conditions, usually characterized by impairment of an individual's normal cognitive, emotional, or behavioral functioning, and caused by physiological or psychosocial factors.mental disease mental disorder
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for mental disorder
[ mĕn′tl ]
Any of various psychiatric disorders or diseases, usually characterized by impairment of thought, mood, or behavior.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.