de·​lu·​sion | \ di-ˈlü-zhən How to pronounce delusion (audio) , dē- \

Definition of delusion

1a : something that is falsely or delusively believed or propagated under the delusion that they will finish on schedule delusions of grandeur
b psychology : a persistent false psychotic belief regarding the self or persons or objects outside the self that is maintained despite indisputable evidence to the contrary the delusion that someone was out to hurt him also : the abnormal state marked by such beliefs
2 : the act of tricking or deceiving someone : the state of being deluded … accused the Bohemian of having practised the most abominable arts of delusion among the younger brethren.— Walter Scott

Other Words from delusion

delusional \ di-​ˈlüzh-​nəl How to pronounce delusion (audio) , dē-​ , -​ˈlü-​zhə-​nᵊl \ adjective
delusionary \ di-​ˈlü-​zhə-​ˌner-​ē How to pronounce delusion (audio) , dē-​ \ adjective

Choose the Right Synonym for delusion

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 delusion in a Sentence

He has delusions about how much money he can make at that job. He is living under the delusion that he is incapable of making mistakes. She is under the delusion that we will finish on time. As the illness progressed, his delusions took over and he had violent outbursts.
Recent Examples on the Web Folie à Deux, which references a delusion or mental illness shared by two people, also suggests that Joker may also team up with another supervillain – possibly his sometime-girlfriend Harley. Jen Juneau,, 14 June 2022 Their failures highlight the limits, if not the delusion, of that vision. Nicole Hemmer, CNN, 3 June 2022 Since there was nothing of economic value driving up crypto prices, only mass delusion, there hasn’t been much to cushion their descent. Andy Kessler, WSJ, 15 May 2022 Many leaders allow their lives to become guided by delusion. Anthony Silard, Fortune, 10 May 2022 In moving up a weight class and selecting Bivol as his opponent, Álvarez crossed that invisible line that separates confidence from delusion, courage from hubris. Houston Mitchell, Los Angeles Times, 9 May 2022 Through Noé’s lens, modern life appears diminished; the streets are portrayed as dangerous chaos; despair is endemic; hope, a sad delusion. Richard Brody, The New Yorker, 28 Apr. 2022 The incident, dismissed by many as a hysterical woman’s delusion, became only a footnote in the constitutional crisis of the moment. Kellie B. Gormly, Smithsonian Magazine, 21 Apr. 2022 Unable to escape the delusion that her mother could become a parent like the ones other people seemed to have, Krouse became increasingly unmoored. Washington Post, 29 Mar. 2022 See More

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

First Known Use of delusion

15th century, in the meaning defined at sense 2

History and Etymology for delusion

Middle English, from Late Latin delusion-, delusio, from deludere — see delude

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The first known use of delusion was in the 15th century

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Last Updated

23 Jun 2022

Cite this Entry

“Delusion.” Dictionary, Merriam-Webster, Accessed 30 Jun. 2022.

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More Definitions for delusion


de·​lu·​sion | \ di-ˈlü-zhən How to pronounce delusion (audio) \

Kids Definition of delusion

: a false belief that continues in spite of the facts "You might be laboring under the delusion that the entire … world is impressed with you …"— J. K. Rowling, Harry Potter and the Goblet of Fire


de·​lu·​sion | \ di-ˈlü-zhən How to pronounce delusion (audio) \

Medical Definition of delusion

1a : the act of deluding : the state of being deluded
b : an abnormal mental state characterized by the occurrence of psychotic delusions
2 : a false belief regarding the self or persons or objects outside the self that persists despite the facts and occurs in some psychotic states — compare hallucination sense 1, illusion sense 2a

More from Merriam-Webster on delusion

Nglish: Translation of delusion for Spanish Speakers

Britannica English: Translation of delusion for Arabic Speakers Encyclopedia article about delusion


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