psychosis

American  

[sahy-koh-sis] / saɪˈkoʊ sɪs /

noun

Psychiatry.

plural

psychoses

1. a mental disorder characterized by symptoms, such as delusions or hallucinations, that indicate impaired contact with reality.

2. any severe form of mental disorder, as schizophrenia or paranoia.

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psychosis British  

/ saɪˈkəʊsɪs /

noun

1. any form of severe mental disorder in which the individual's contact with reality becomes highly distorted Compare neurosis

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psychosis Scientific  

/ sī-kō′sĭs /

plural

psychoses

1. A mental state caused by psychiatric or organic illness, characterized by a loss of contact with reality and an inability to think rationally. A psychotic person often behaves inappropriately and is incapable of normal social functioning.

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psychosis Cultural  

1. A severe mental disorder, more serious than neurosis, characterized by disorganized thought processes, disorientation in time and space, hallucinations, and delusions. Paranoia, manic depression, megalomania, and schizophrenia are all psychoses. One who suffers from psychosis is psychotic.

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Etymology

Origin of psychosis

First recorded in 1840–50, psychosis is from the Late Greek word psȳ́chōsis animation, principle of life. See psych-, -osis

Compare meaning

How does psychosis compare to similar and commonly confused words? Explore the most common comparisons:

• neurosis vs. psychosis

Example Sentences

For years, researchers have proposed that psychosis may result from a reduced ability to update beliefs when new information becomes available.

From Science Daily • Apr. 3, 2026

There is a growing body of legal cases alleging AI-related harms, including psychosis External link, often citing heavy engagement with chatbots.

From Barron's • Mar. 26, 2026

She said her family were told there were no available beds in Leeds - Yorkshire's only MBU - with Lizzy sent to the closest available unit able to treat psychosis and severe postnatal depression.

From BBC • Mar. 8, 2026

It adds to a growing body of legal cases alleging artificial-intelligence-related harms, including psychosis.

From The Wall Street Journal • Mar. 4, 2026

They explained that the psychosis and other serious mental health problems that burdened Mr. Jenkins could lead to dangerous behavior, but this behavior was a manifestation of serious illness, not a reflection of his character.

From "Just Mercy" by Bryan Stevenson

Related Words

• absurdity
• alienation
• craziness
• folly
• frenzy
• hysteria
• irresponsibility
• lunacy
• madness
• mental disorder