Definitions

delusion

[dih-loo-zhuhn] / dɪˈlu ʒən /

NOUN

misconception, misbelief

Synonyms

STRONGEST

deception fantasy hallucination illusion pipe dream

STRONG

apparition blunder casuistry chicanery daydream deceptiveness dream error fallacy fancy figment ghost lapse mirage misapprehension mistake oversight phantasm phantom self-deception shade speciousness spuriousness trickery trip vision

WEAK

eidolon false impression fool's paradise head trip ignis fatuus optical illusion

Antonyms

STRONGEST

fact reality truth

STRONG

accuracy actuality being certainty correction fix honesty right success

WEAK

surety

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.

He is the co-author of "The Cult of We: WeWork, Adam Neumann and the Great Startup Delusion," published in summer 2021.

From The Wall Street Journal • Jan. 30, 2026

Several exhibited Capgras Delusion, which causes someone to believe that a person close to them has been replaced by an identical-looking imposter.

From BBC • Jan. 10, 2026

That ability to play off each other's strengths has an obvious, and extremely positive, impact on how "Heavenly Delusion" looks and feels.

From Salon • Dec. 23, 2023

Delusion is one of the more upscale haunted attractions in SoCal.

From Los Angeles Times • Oct. 18, 2023

Delusion is much stronger than illusion, and implies that Cyril has been misled or deceived—in this case, by himself. alternate/alternative.

From "Woe Is I" by Patricia T. O'Conner

Vocabulary lists containing delusion

Night

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