psychosis

noun

psy·​cho·​sis sī-ˈkō-səs How to pronounce psychosis (audio)
plural psychoses sī-ˈkō-ˌsēz How to pronounce psychosis (audio)
Synonyms of psychosisnext
: a serious mental illness (such as schizophrenia) characterized by defective or lost contact with reality often with hallucinations or delusions

Examples of psychosis in a Sentence

The patient suffers from some kind of psychosis.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Postpartum psychosis is considered a psychiatric emergency, according to the American College of Obstetricians and Gynecologists. — ABC News, 4 Sep. 2026 Cruz has discretion to determine the future of a case that has gripped the nation and ignited a furious debate about the issue of postpartum depression and postpartum psychosis. — Rebecca Cohen, NBC news, 4 Sep. 2026 Reddington argued in opening statements that Clancy experienced postpartum depression and psychosis, and heard a male voice telling her to commit the killings. — Christopher Cann, USA Today, 3 Sep. 2026 During the state’s closing arguments, Assistant District Attorney Jennifer Sprague claimed Clancy was depressed and suicidal, but not suffering from psychosis. — Liam Quinn, PEOPLE, 3 Sep. 2026 See All Example Sentences for psychosis

Word History

Etymology

New Latin

First Known Use

1847, in the meaning defined above

Time Traveler
The first known use of psychosis was in 1847

Rhymes for psychosis

See All Rhymes for psychosis

Browse Nearby Words

psychosexuality
psychosis
psychosocial
See all Nearby Words

Cite this Entry

“Psychosis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psychosis. Accessed 7 Sep. 2026.

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Kids Definition

psychosis

noun
psy·​cho·​sis sī-ˈkō-səs How to pronounce psychosis (audio)
plural psychoses -ˈkō-ˌsēz How to pronounce psychosis (audio)
: a serious mental illness marked by loss of or greatly lessened ability to test whether what one is thinking and feeling about the real world is really true

Medical Definition

psychosis

noun
psy·​cho·​sis sī-ˈkō-səs How to pronounce psychosis (audio)
plural psychoses -ˌsēz How to pronounce psychosis (audio)
: a serious mental illness (as schizophrenia) characterized by defective or lost contact with reality often with hallucinations or delusions

More from Merriam-Webster on psychosis

Thesaurus: All synonyms and antonyms for psychosis

Britannica.com: Encyclopedia article about psychosis

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