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What artistic painting technique creates the optical illusion of realistic three-dimensionality?

illusion

American  
[ih-loo-zhuhn] / ɪˈlu ʒən /

noun

  • illusions
    plural
  1. something that deceives by producing a false or misleading impression of reality.

    Synonyms:
    chimera, fantasy, aberration
  2. the state or condition of being deceived; misapprehension.

  3. an instance of being deceived.

  4. Psychology. a perception, as of visual stimuli optical illusion, that represents what is perceived in a way different from the way it is in reality.

  5. a very thin, delicate tulle of silk or nylon having a cobwebbed appearance, for trimmings, veilings, and the like.

  6. Obsolete. the act of deceiving; deception; delusion.


illusion British  
/ ɪˈluːʒən /

noun

  1. a false appearance or deceptive impression of reality

    the mirror gives an illusion of depth

  2. a false or misleading perception or belief; delusion

    he has the illusion that he is really clever

  3. psychol a perception that is not true to reality, having been altered subjectively in some way in the mind of the perceiver See also hallucination

  4. a very fine gauze or tulle used for trimmings, veils, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

illusion, hallucination, delusion refer to false perceptions or ideas. An illusion is a false mental image produced by misinterpretation of things that actually exist: A mirage is an illusion produced by reflection of light against the sky. A hallucination is a perception of a thing or quality that has no physical counterpart: Under the influence of LSD, Terry had hallucinations that the living-room floor was rippling. A delusion is a persistent false belief: A paranoiac has delusions of persecution.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of illusion

First recorded in 1300–50; Middle English from Latin illūsiōn- (stem of illūsiō ) “irony, mocking,” equivalent to illūs(us), past participle of illūdere “to mock, ridicule” ( il- il- 1 + lūd- play ( see ludicrous) + -tus past participle suffix) + -iōn- -ion

Explanation

An illusion is something that isn't real. It may look real, but it's actually fake — just a crafty construction or fantasy. Like the old rabbit-out-of-the-hat trick practiced by magicians around the globe. An illusion is an act of deception. Some optical illusions are pretty cool to watch, but an illusion can also point to an erroneous belief or false perception of reality, which is where you start getting into hallucination territory — seeing things that aren't there. You can give the illusion that you’re fascinated by your professor’s lecture by chewing on your pencil, furrowing your brow, and making sure to nod enthusiastically every so often.

Keep Reading on Vocabulary.com

Vocabulary lists containing illusion

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.

See Examples For:

And Skylar Fox’s illusion design adds an element of visual sorcery.

From Los Angeles Times ● Sep. 22, 2026

They were guilty of what economists refer to as te money illusion — confusing nominal dollar amounts with real, or inflation-adjusted, levels.

From MarketWatch ● Sep. 14, 2026

This term in particular shattered that illusion for me.

From Slate ● Aug. 31, 2026

A clean break turned out to be an illusion.

From The Wall Street Journal ● Aug. 30, 2026

The illusion of change is so convincing that we share Apollo’s shock at the metamorphosis.

From "History of Art, Volume 1" by H.W. Janson

Parton, who died Tuesday at age 80, made a career out of building illusions she delighted in dismantling.

From Los Angeles Times ● Aug. 26, 2026

As critical as he is of his own government, he has few illusions about the West.

From BBC ● Aug. 13, 2026

“Many students and postdocs lost friends and illusions that week,” Mr. Sheffi writes.

From The Wall Street Journal ● Jul. 8, 2026

"He would never do that, let's not have any illusions," said Tikhanovskaya, who recently returned from a trip to Kyiv.

From Barron's ● Jun. 26, 2026

The young lawyer was on civil, if not close, terms with Durham’s older black leaders, but he labored under no illusions about their willingness to take bold action.

From "The Best of Enemies" by Osha Gray Davidson

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