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

That position is at the core of the legal case brought by Brosseau, which argues that current laws are exclusionary to those with mental illness and therefore unconstitutional.

From BBC • May 15, 2026

I couldn't understand why his trial records made no reference to mental illness, but after the George Daniel case, nothing surprised me.

From "Just Mercy" by Bryan Stevenson

Related Words

• insanity
• mental disorder