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

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

By and large, experts point to systematic failures that leave Americans more vulnerable to mental illness and without access to drug-free interventions, which cost both time and money.

From Salon • May 18, 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

While it is legal in Canada, it is not currently available to those whose sole condition is mental illness.

From BBC • May 15, 2026

Today, over 50 percent of prison and jail inmates in the United States have a diagnosed mental illness, a rate nearly five times greater than that of the general adult population.

From "Just Mercy" by Bryan Stevenson

Related Words

• insanity
• mental disorder