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.
Hathaway’s White Queen floats with sweet highs and dark lows, her heavenly air masking a morbid psychosis. — Chris Feil, Vulture, 1 May 2026 Malek colors him in with shades of anger, tenderness, psychosis, and the sheer pesky individuality of Jimmy. — Owen Gleiberman, Variety, 20 May 2026 As Delphi’s star rises, P Burke becomes enthralled by her and descends into a tech psychosis with disastrous consequences. — Melanie Goodfellow, Deadline, 6 May 2026 Prosecutors at this second trial say Dominguez, diagnosed with schizophrenia, used heavy and frequent doses of marijuana that heightened his psychosis and led to the attacks. — Darrell Smith june 8, Sacbee.com, 8 June 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 8 Jul. 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
Last Updated: - Updated example sentences
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