mental illness

noun

1. any of the various forms of psychosis or severe neurosis.

mental illness

noun

1. 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

mental illness

1. Any of various psychiatric disorders or diseases, usually characterized by impairment of thought, mood, or behavior.

Word History and Origins

Origin of mental illness¹

First recorded in 1960–65

Example Sentences

One of the boys, who the American psychiatrist suspected had a mental illness, was taken to a local psychiatrist for an evaluation.

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And while we may be a nation divided over the causes of the horrific, endless wave of shootings in this country, it’s unassailable that mental illness plays a part.

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But it means many people with conditions such as diabetes, heart disease, respiratory illneses, asthma and severe mental illness will no longer qualify.

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Her erratic behavior had cost her jobs, and she had been treated for mental illness numerous times.

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Advocates, public officials and social media users of both sides condemned the comment, warning that it risked fueling stigma against people experiencing homelessness or mental illness.

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Related Words

• insanity 
• mental disorder