Definition of delusion
1 : 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
2a : something that is falsely or delusively believed or propagated under the delusion that they will finish on schedule delusions of grandeurb 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
delusionalplay \-ˈlüzh-nəl, -ˈlü-zhə-nəl\ adjective
delusionaryplay \-zhə-ˌner-ē\ adjective
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 of delusion from the Web
Many times, the delusion lifts from the patient after several months, but some people do suffer with it for years.
Both opponents fell victim to delusions about bloodless victory without hard fighting.
The movement has been seized by a kind of discrediting madness, in which conspiracy delusions figure prominently.
The brothers wrestle with their parents’ memory loss, anger and delusions.
This probably isn't going to happen because the enemies to the north are literal ice zombies and the ones to the east are fire-breathing dragons, but hey, nobody ever got to sit on the Iron Throne without a little bit of self-delusion.
The anniversary is a moment, in fact, to acknowledge that the Six Day War produced a grand delusion, one that five decades later reveals itself in these books.
He’d also shown early signs of dementia starting in 2015, sometimes suffering delusions, which had become much worse in the last month.
There was a sort of delusion based on overly optimistic ideas about Trump.
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.
Origin and Etymology of delusion
Middle English, from Late Latin delusion-, delusio, from deludere —see delude
First Known Use: 15th century
Synonym Discussion of delusion
DELUSION Defined for English Language Learners
Definition of delusion for English Language Learners
: a belief that is not true : a false idea
: a false idea or belief that is caused by mental illness
DELUSION Defined for Kids
Definition of delusion for Students
: 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, Goblet of Fire
Medical Definition of delusion
1a: the act of deluding : the state of being deludedb: an abnormal mental state characterized by the occurrence of psychotic delusions
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