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

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

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

Wil worked as a nurse in a hospital after Theo died, but she also suffered from mental illness.

From "Vincent and Theo: The Van Gogh Brothers" by Deborah Heiligman

Related Words

• insanity
• mental disorder