psy·​cho·​sis | \ sī-ˈkō-səs How to pronounce psychosis (audio) \
plural psychoses\ sī-​ˈkō-​ˌsēz How to pronounce psychoses (audio) \

Definition of psychosis

: 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

There are also some studies in humans demonstrating that CBD can decrease psychosis and schizophrenia-like symptoms. Kaitlyn Pirie, Woman's Day, "What Is CBD, and Why Is Everybody Talking About It?," 15 Feb. 2019 Hallucinations are commonly experienced by people experiencing psychosis or those who have schizophrenia, people on a hallucinogen, or by people who have dementia. Kate Gardner, SELF, "What It’s Like to Be So Sleep Deprived That You Hallucinate," 14 Feb. 2019 The link between marijuana and violence doesn’t appear limited to people with pre-existing psychosis. Alex Berenson, WSJ, "Marijuana Is More Dangerous Than You Think," 4 Jan. 2019 In 2017, Faber was diagnosed with acute psychosis with a marked stressor, and left her city job. Heidi Groover, The Seattle Times, "Sen. Joe Fain’s accuser: ‘I’m done being silent’," 1 Oct. 2018 When people stop using it, withdrawal symptoms can include anxiety, fatigue, severe depression, psychosis, and intense drug cravings. Alexis Stevens, The Seattle Times, "Georgia tallies meth’s toll: Nearly 20 percent of those killed by police in state test positive for it," 20 Nov. 2018 There is longstanding data indicating association of marijuana use with psychosis, particularly in patients with pre-existing mental-health conditions. WSJ, "Should the Feds Join the Trend to Legalize Pot?," 8 Nov. 2018 And one of us reads what would be considered by most a normal number of books in a year, while the other’s intake borders on psychosis. WSJ, "Who Read What in 2018: Actors and Entertainers," 10 Dec. 2018 If someone has symptoms that result in psychosis or hospitalization, that’s also considered a manic episode. Jacqueline Andriakos, SELF, "This Is What a Bipolar Manic Episode Feels Like," 7 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'psychosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of psychosis

1847, in the meaning defined above

History and Etymology for psychosis

New Latin

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Last Updated

17 Mar 2019

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Time Traveler for psychosis

The first known use of psychosis was in 1847

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English Language Learners Definition of psychosis

: a very serious mental illness that makes you behave strangely or believe things that are not true


psy·​cho·​sis | \ sī-ˈkō-səs How to pronounce psychosis (audio) \
plural psychoses\ -​ˌsēz How to pronounce psychoses (audio) \

Medical Definition of psychosis

: a serious mental illness (as schizophrenia) characterized by defective or lost contact with reality often with hallucinations or delusions

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More from Merriam-Webster on psychosis

Rhyming Dictionary: Words that rhyme with psychosis

Thesaurus: All synonyms and antonyms for psychosis

Spanish Central: Translation of psychosis

Nglish: Translation of psychosis for Spanish Speakers Encyclopedia article about psychosis

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