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
The number of inpatient beds for people with a serious mental illness nationwide has plummeted.
—
CBS News, 28 Apr. 2025
Prosecution: Autism doesn’t prevent death penalty in any state
Arguments that other states, such as Ohio and Kentucky, expanded their laws to bar people with serious mental illness from facing the death penalty don’t apply, Hippler said.
—Alex Brizee, Idaho Statesman, 25 Apr. 2025
A number of violent incidents involving those with serious mental illness have added fuel to the debate over how to tackle the city’s mental health problem.
—Josephine Stratman, New York Daily News, 18 Apr. 2025
In 2022, California started offering nontraditional health benefits through Medicaid — including help finding jobs — for enrollees experiencing homelessness or serious mental illness, or who are otherwise at risk of avoidable emergency room care.
—Phil Galewitz, NPR, 15 Apr. 2025
See All Example Sentences for mental illness
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CBS News, 28 Apr. 2025
Prosecution: Autism doesn’t prevent death penalty in any state
Arguments that other states, such as Ohio and Kentucky, expanded their laws to bar people with serious mental illness from facing the death penalty don’t apply, Hippler said.
—Alex Brizee, Idaho Statesman, 25 Apr. 2025
A number of violent incidents involving those with serious mental illness have added fuel to the debate over how to tackle the city’s mental health problem.
—Josephine Stratman, New York Daily News, 18 Apr. 2025
In 2022, California started offering nontraditional health benefits through Medicaid — including help finding jobs — for enrollees experiencing homelessness or serious mental illness, or who are otherwise at risk of avoidable emergency room care.
—Phil Galewitz, NPR, 15 Apr. 2025
See All Example Sentences for mental illness
Cite this Entry
“Mental illness.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mental%20illness. Accessed 1 May. 2025.
Copy CitationMedical 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
Ellen L. Bassuk, Scientific AmericanCatatonia 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
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
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
Barbara M. Swanson, Careers in Health Care
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