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

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 After all the despair, the piling up of glitzy delusion, there’s a feeling of redemption to it connected to what a good movie can do. Owen Gleiberman, Variety, 16 May 2024 But amid the psychosis, the singer suffered from extreme paranoia, fear, and delusions that steadily separated him from reality. Ethan Millman, Rolling Stone, 15 May 2024 See all Example Sentences for delusion 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'delusion.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 21 May. 2024.

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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