psychosis

noun

psy·​cho·​sis sī-ˈkō-səs 

plural psychoses sī-ˈkō-ˌsēz 

: 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

Instead, Ferguson watched as her once bright-eyed, handsome son sank into disheveled psychosis, bouncing between family members' homes, homeless shelters, jails, clinics, emergency rooms and Ohio's regional psychiatric hospitals. —Sarah Jane Tribble, NPR, 22 Dec. 2025

As a result, spiritual psychosis—where a mental health crisis is perceived by the individual as a spiritual revelation—can occur. —Lisa Stardust, Vogue, 22 Dec. 2025

Studies have shown that use of higher-concentration marijuana is associated with serious mental-health outcomes, such as psychosis. —Nicholas Florko, The Atlantic, 19 Dec. 2025

But by OpenAI’s own numbers, that amounts to some half a million people regularly exhibiting mania or psychosis on the platform. —Charlie Campbell, Time, 11 Dec. 2025

Word History

Etymology

New Latin

First Known Use

1847, in the meaning defined above

Rhymes for psychosis

• cirrhosis
• fibrosis
• gliosis
• hypnosis
• ichthyosis
• ketosis
• kurtosis
• lordosis
• meiosis
• miosis
• mitosis
• mycosis

Kids Definition

psychosis

noun

psy·​cho·​sis sī-ˈkō-səs 

plural psychoses -ˈkō-ˌsēz 

: 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 

plural psychoses -ˌsēz 

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