delusion

noun

de·​lu·​sion di-ˈlü-zhən How to pronounce delusion (audio)
dē-
1
a
: 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
delusional
di-ˈlüzh-nəl How to pronounce delusion (audio)
dē-
-ˈlü-zhə-nᵊl
adjective
delusionary 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

Example Sentences

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 For big tech companies like Meta, there was the delusion, which Mr. Zuckerberg acknowledged when announcing layoffs of more than 11,000 employees, that the world would change little once pandemic lockdowns lifted. Christopher Mims, WSJ, 19 Nov. 2022 Authorities believe 42-year-old East Bay resident David DePape forced entry into the home looking for Nancy Pelosi, who has been a central target of far-right conspiracy theories such as the QAnon mass delusion. Demian Bulwa, San Francisco Chronicle, 30 Oct. 2022 There is a trace of delusion in Johnson’s idea that a superhero movie could herald his return to form. Lauren Michele Jackson, The New Yorker, 29 Oct. 2022 Temporal disorientation and historical delusion are now the province of politics rather than medicine. Aaron Timms, The New Republic, 31 Oct. 2022 It’s not a mass delusion or faulty collective memory. Andrew Van Dam, Washington Post, 21 Oct. 2022 The laissez-faire economists Friedrich Hayek and Milton Friedman were, for Mr. Soll, peddlers of a dangerous delusion. Barton Swaim, WSJ, 9 Sep. 2022 Folie à Deux, which references a delusion or mental illness shared by two people, suggests that Joker may also team up with another supervillain — possibly his sometimes-girlfriend Harley. Amanda Taylor, Peoplemag, 8 Oct. 2022 After all, self-awareness is the infrathin distinction between delusion and imagination. Jonathon Keats, Forbes, 20 May 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.

Word History

Etymology

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

First Known Use

15th century, in the meaning defined at sense 2

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

Dictionary Entries Near delusion

Cite this Entry

“Delusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/delusion. Accessed 4 Dec. 2022.

Kids Definition

delusion

noun

de·​lu·​sion di-ˈlü-zhən How to pronounce delusion (audio)
1
: the act of deluding : the state of being deluded
2
a
: a mistaken or misleading belief
b
: a false belief that persists despite evidence proving it false and occurs especially in some mentally disturbed states
delusional
-ˈlüzh-nəl How to pronounce delusion (audio)
-ən-ᵊl
adjective

Medical Definition

delusion

noun

de·​lu·​sion di-ˈlü-zhən How to pronounce delusion (audio)
1
a
: 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

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