mental illness


noun

any of the various forms of psychosis or severe neurosis.

Origin of mental illness

First recorded in 1960–65
Also called mental disorder, mental disease.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for mental disorder (1 of 2)

mental disorder

noun

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 disorder

mentally disordered, adjective

British Dictionary definitions for mental disorder (2 of 2)

mental illness

noun

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)

mental disorder

n.

mental illness

Medical definitions for mental disorder (2 of 2)

mental illness

n.

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

mental illness
[ mĕntl ]

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.