mental illness

American  

noun

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

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mental illness British  

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

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mental illness Scientific  

/ mĕn′tl /

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

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Etymology

Origin of mental illness

First recorded in 1960–65

Example Sentences

The result can be heard in songs like the hard-driving “Is It Real?” in which Hollywell roars about mental illness and divine intervention, while Santos coats it all in steel honey.

From Salon • Jun. 5, 2026

Maybe Pratt can actually deliver on his promise of a “treatment-led recovery model that addresses mental illness and addiction as the primary drivers of chronic homelessness.”

From Los Angeles Times • Jun. 4, 2026

Its hero, Wilbur Budd, is grappling not with mental illness, as Nora was, but with grief and missed opportunities.

From The Wall Street Journal • May 25, 2026

Maddock and Smucny have long studied how brain chemistry is connected to mental illness using proton magnetic resonance spectroscopy, also known as 1H-MRS.

From Science Daily • May 16, 2026

By the time she had turned thirty, prison doctors diagnosed her with multiple sclerosis, intellectual disability, and mental illness related to trauma.

From "Just Mercy" by Bryan Stevenson

Related Words

• insanity
• mental disorder