hal·​lu·​ci·​na·​tion | \ hə-ˌlü-sə-ˈnā-shən How to pronounce hallucination (audio) \

Definition of hallucination

1a : perception of objects with no reality usually arising from disorder of the nervous system or in response to drugs (such as LSD) was having hallucinations
b : the object so perceived wasn't sure if the rain was real or a hallucination
2 : an unfounded or mistaken impression or notion : delusion

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Choose the Right Synonym for hallucination

delusion, illusion, hallucination, mirage mean something that is believed to be true or real but that is actually false or unreal. delusion implies an inability to distinguish between what is real and what only seems to be real, often as the result of a disordered state of mind. delusions of persecution illusion implies a false ascribing of reality based on what one sees or imagines. an illusion of safety hallucination implies impressions that are the product of disordered senses, as because of mental illness or drugs. suffered from terrifying hallucinations mirage in its extended sense applies to an illusory vision, dream, hope, or aim. claimed a balanced budget is a mirage

Examples of hallucination in a Sentence

He could not tell if what he was seeing was real or if it was a hallucination. He has been having hallucinations due to the medication.
Recent Examples on the Web What a ridiculous hallucination this was, what an indestructible pleasure, what an unforeseeable gift. Jia Tolentino, The New Yorker, "The Improbable Insanity of “Cats”," 16 Dec. 2019 The high can last for up to 16 hours and often comes with agitation, hallucinations and paranoia, sometimes causing users to become aggressive or violent. Dominic Fracassa, SFChronicle.com, "For SF meth users, a sobering center is planned. What would that look like?," 26 Oct. 2019 According to the National Institute on Drug Abuse and Center on Addiction, dabbing can result in symptoms that include rapid heartbeat, loss of consciousness and psychotic reactions such as paranoia and hallucinations. Billy Kobin, The Courier-Journal, "Kentucky high school students were hospitalized after vaping from a 'dab pen,' police say," 26 Sep. 2019 Spice can trigger psychotic effects like paranoia and hallucinations. AZCentral.com, "Police shootings in Arizona," 10 Sep. 2019 Christians pushed back on any hallucinations or psychosis diagnoses, something McKinney brought up to other therapists. Sam Tabachnik, The Denver Post, "STEM shooting suspect low-to-medium risk of violence, good candidate for juvenile facility, psychologist says," 25 Nov. 2019 The punishment, which has become more controversial over time, can cause severe depression, distortions and hallucinations, nightmares and lower levels of brain function, according to the Vera Institute of Justice. Crystal Hill, Indianapolis Star, "Indiana will pay inmate $100K for each year he spent in solitary, lawyers say," 11 Nov. 2019 Lastly, a small group will first present with neuropsychiatric symptoms, which can include hallucinations, behavioral problems, and difficulty with complex mental activities, also leading to an initial diagnosis of DLB. Mike Oliver | Moliver@al.com, al, "10 things you should know about Lewy body dementia," 30 Oct. 2019 But a schizoaffective disorder diagnosis also calls for at least two weeks of having delusions and/or hallucinations in the absence of a mood episode. Carolyn L. Todd, SELF, "What Mental Health Experts Want You to Know About Schizoaffective Disorder," 19 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hallucination.' 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 hallucination

1629, in the meaning defined at sense 1a

History and Etymology for hallucination

see hallucinate

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Time Traveler for hallucination

Time Traveler

The first known use of hallucination was in 1629

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Statistics for hallucination

Last Updated

10 Jan 2020

Cite this Entry

“Hallucination.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/hallucination. Accessed 18 January 2020.

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More Definitions for hallucination


How to pronounce hallucination (audio)

English Language Learners Definition of hallucination

: something (such as an image, a sound, or a smell) that seems real but does not really exist and that is usually caused by mental illness or the effect of a drug


hal·​lu·​ci·​na·​tion | \ hə-ˌlü-sə-ˈnā-shən How to pronounce hallucination (audio) \

Kids Definition of hallucination

: the seeing of objects or the experiencing of feelings that are not real but are usually the result of mental disorder or the effect of a drug


hal·​lu·​ci·​na·​tion | \ hə-ˌlüs-ᵊn-ˈā-shən How to pronounce hallucination (audio) \

Medical Definition of hallucination

1 : a perception of something (as a visual image or a sound) with no external cause usually arising from a disorder of the nervous system (as in delirium tremens or in functional psychosis without known neurological disease) or in response to drugs (as LSD) — compare delusion sense 2, illusion sense 2a
2 : the object of a hallucinatory perception

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Comments on hallucination

What made you want to look up hallucination? Please tell us where you read or heard it (including the quote, if possible).


experienced by way of someone else

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