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 Nobody really wants a tool that can make anything, because such a need is a theoretical delusion, a capitalist fantasy, or both. Ian Bogost, The Atlantic, 13 Jan. 2023 There was a sense that this was all a strange delusion. Jim Farber, Vulture, 5 May 2022 But their injuries and experiences were inconsistent with mass psychogenic illness, and the individuals weren't all in contact with each other, which would be necessary for a collective delusion to spread. Beth Mole, Ars Technica, 3 Feb. 2022 Danhausen’s dubious command of occult forces is only one aspect of his absurd presentation, which blurs the line between what is supposed to be real in the fictive world of pro wrestling and what is supposed to be his character’s own delusion. Peter Rubin, Longreads, 10 Jan. 2023 Danhausen’s dubious command of occult forces is only one aspect of his absurd presentation, which blurs the line between what is supposed to be real in the fictive world of pro wrestling and what is supposed to be his character’s own delusion. Dan Brooks, New York Times, 10 Jan. 2023 Munger said that combination of fraud and delusion was to blame. Chris Morris, Fortune, 15 Nov. 2022 It’s part Devo, part delusion, and all Brucio goodness. Jill Krajewski, Vulture, 24 May 2022 If you are tempted, even now, by the lingering romantic delusion that there might be some grandeur, or finesse, in the prospect of a creative mind under siege, the ordeal of Ivor Gurney will set you right. Anthony Lan, The New Yorker, 5 July 2021 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 1 Feb. 2023.

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

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