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

From one angle or another, I’ve been writing about the intersection of homelessness, mental illness and addiction for a couple of decades, and I still have a lot to learn.

From Los Angeles Times • Jun. 6, 2026

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

The just-quirky-girls-at-a-country-club mood does eventually turn darker, but the musical, like some other works of art about mental illness, often falls into the trap of romanticizing it.

From The Wall Street Journal • Jun. 5, 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

Some of them like him and—he thinks—know of mental illness firsthand and so understand him.

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

Related Words

• insanity
• mental disorder