mental illness

noun

variants or mental disorder or less commonly mental disease
: any of a broad range of medical conditions (such as major depression, schizophrenia, obsessive compulsive disorder, or panic disorder) that are marked primarily by sufficient disorganization of personality, mind, or emotions to impair normal psychological functioning and cause marked distress or disability and that are typically associated with a disruption in normal thinking, feeling, mood, behavior, interpersonal interactions, or daily functioning
mentally ill adjective

Examples of mental illness in a Sentence

Recent Examples on the Web This book is full of resources that help adults explain to children the behaviors associated with mental illness. Nafeesah Allen, Parents, 26 Nov. 2023 Carter said her goal was for the book to help dispel stigmas that cause people with mental illness to hide from help. Caleigh Bartash, ABC News, 22 Nov. 2023 But such saturated awareness of mental health doesn’t automatically translate into a robust cultural understanding of mental illness or how it’s managed. Ilana Masad, The Atlantic, 20 Nov. 2023 Rosalynn's support of mental health services and awareness is a reminder to us all that the challenge of mental illness is still a great need. Aliza Chasan, CBS News, 19 Nov. 2023 The Pulitzer Prize-winning play is about a family who are brilliant at math but also face challenges of mental illness. David L. Coddon, San Diego Union-Tribune, 17 Nov. 2023 Against the Death Penalty, Texas executes prisoner with history of mental illness Oct. 11, 2023 After an independent investigation, the Los Angeles district attorney’s office agreed and asked the court to free Solorio. Salvador Hernandez, Los Angeles Times, 10 Nov. 2023 But sometimes that wiring results in unhealthy connections becoming strengthened, resulting in tenacious mental illnesses like long-lasting depression or anxiety. Linda Carroll, NBC News, 29 Oct. 2023 Not just run-of-the-mill discontent over darker evenings, but the makings of an actual mental illness. WIRED, 15 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mental illness.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1724, in the meaning defined above

Time Traveler
The first known use of mental illness was in 1724

Dictionary Entries Near mental illness

Cite this Entry

“Mental illness.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mental%20illness. Accessed 30 Nov. 2023.

Medical Definition

mental illness

noun
variants or mental disorder also mental disease
: any of a broad range of medical conditions (such as major depression, schizophrenia, obsessive compulsive disorder, or panic disorder) that are marked primarily by sufficient disorganization of personality, mind, or emotions to impair normal psychological functioning and cause marked distress or disability and that are typically associated with a disruption in normal thinking, feeling, mood, behavior, interpersonal interactions, or daily functioning
Some homeless families are also hindered by substance abuse and mental illness.Ellen L. Bassuk, Scientific American
Catatonia is usually an expression of mental disorders like bipolar disorder or schizophrenia, but it could also come from other medical problems, such as a brain tumor.Forrest Wickman, The Pittsburgh Post-Gazette
mental diseases such as schizophrenia and manic depression may either involve more than one gene or may result from a complex mix of genetic predisposition and environmental rotten luck.Natalie Angier, The New York Times Book Review
mentally ill adjective
mentally ill patients
Mental health workers … perform a wide variety of therapeutic, supportive, and preventative functions for persons who are mentally ill and developmentally disabled. Barbara M. Swanson, Careers in Health Care

Legal Definition

mental illness

noun
mental ill·​ness
1
2
: a mental condition marked primarily by sufficient disorganization of personality, mind, and emotions to seriously impair the normal psychological and often social functioning of the individual

called also mental disorder

More from Merriam-Webster on mental illness

Last Updated: - Updated example sentences
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