noun
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a mistaken or misleading opinion, idea, belief, etc
he has delusions of grandeur
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psychiatry a belief held in the face of evidence to the contrary, that is resistant to all reason See also illusion hallucination
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the act of deluding or state of being deluded
Usage
What is a delusion? A delusion is a false belief or opinion, especially one held in resistance to strong evidence against it, as in Even after losing five straight championships, Heather still had the delusion that she was the best in the world.In psychiatry, delusion is used to mean an unshakeable belief in something that isn’t true. They believe it because they have a mental disorder, such as schizophrenia.More generally, delusion can be used to mean an act of deluding, as in The crowd didn’t fall for the swindler’s attempts at delusion.Delusion can also refer to the state of being deluded, as in The emperor’s delusion was the work of the evil, scheming vizier.Delusion is similar to the words illusion and hallucination, which also describe false beliefs or experiences. An illusion is a false image that is a result of a distortion or manipulation of actual things. For example, makeup can create the illusion that a person is younger than they actually are.A hallucination is a false sensory experience that isn’t rooted in reality at all. On the other hand, a delusion is often somewhat based on reality but a person’s belief is inaccurate due to wrong information or their own hubris.Example: Despite his low test scores, Gerard strongly believed the delusion that he was the smartest kid in the class.
Related Words
See illusion.
Other Word Forms
- delusional adjective
- delusionary adjective
- delusive adjective
- delusively adverb
- delusiveness noun
- delusory adjective
- predelusion noun
Etymology
Origin of delusion
First recorded in 1375–1425; late Middle English, from Latin dēlūsiōn- (stem of dēlūsiō ), equivalent to dēlūs(us) (past participle of dēlūdere; delude ) + -iōn- -ion
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
“But he told me, no. It had to be done. He told me, hope is another word for delusion.”
From Literature
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Schizophrenia, which can involve hallucinations, delusions, and disorganized thinking, has often been linked to this mechanism.
From Science Daily
A U.K. police chief is under fire after admitting a delusion from Microsoft Copilot produced incorrect evidence.
From MarketWatch
She blinked hard, expecting them to disappear, for them to be a delusion brought on by her first sickness in nearly a hundred years.
From Literature
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He was forced out because fans and board had delusions of grandeur after Moyes won the club silverware and now it's a relegation battle the club look ill equipped for.
From BBC
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.