Definition of illusion in English:

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Pronunciation: /iˈlo͞oZHən/


1A thing that is or is likely to be wrongly perceived or interpreted by the senses: the illusion makes parallel lines seem to diverge by placing them on a zigzag-striped background
More example sentences
  • Hallucinations and illusions are disturbances of perception that are common in people suffering from schizophrenia.
  • The intoxicated state is characterized by illusions, visual hallucinations and bodily distortions.
  • They also experienced visual illusions such as real objects appearing to move or pulsate.
mirage, hallucination, apparition, figment of the imagination, trick of the light, trompe l'oeil;
deception, trick, smoke and mirrors
(magic) trick, conjuring trick;
(illusions) magic, conjuring, sleight of hand, legerdemain
1.1A deceptive appearance or impression: the illusion of family togetherness the tension between illusion and reality
More example sentences
  • Unfortunately, Britain and Europe are all too eager to pretend that such illusions are reality.
  • The progress of the film is a progress through illusion and deception toward reality and truth.
  • However, you will live in a metaphysical world, where reality and illusions will be so skewed that they will appear to be identical.
appearance, impression, semblance;
misperception, false appearance
rare simulacrum
1.2A false idea or belief: he had no illusions about the trouble she was in
More example sentences
  • Man and house are thus a perfect match, as all the characters trapped in their own illusions and false expectations of Sancher end up more hurt than healed.
  • Our world will appear to crumble as we know it, as distractions, false voices, illusions and misconceptions will be taken away from us.
  • Believing that our beliefs are illusions, however, is self-refuting.
delusion, misapprehension, misconception, false impression;
fantasy, fancy, dream, chimera;
fool's paradise, self-deception;
false consciousness



be under the illusion that

Believe mistakenly that: the world is under the illusion that the original painting still hangs in the Winter Palace
More example sentences
  • ‘No one should be under the illusion that because a plan exists in one form today that it will be that way forever,’ he said.
  • The Popular Unity's supporters were under the illusion that once in power it would fulfil the promise of profound political and socio-economic change.
  • Progressives have been under the illusion that if only people understood the facts, we'd be fine.

be under no illusion (or illusions)

Be fully aware of the true state of affairs.
Example sentences
  • She says she has been greatly impressed with the efficiency of the Dundee operation but is under no illusions about the challenges facing a factory on the northern fringes of Europe.
  • But I'm under no illusions, it could be taken away at any point, so I just grab it with both hands.
  • The 35-year-old is under no illusions about his situation.



Pronunciation: /-ZHənl/
Example sentences
  • The illusional architecture was then painted by Orazio's associate, Agostino Tassi, a master of perspective, who had been engaged to teach that art to Artemisia.
  • Anyway, we know the extent of Pennyn's powers is at least illusional.


Middle English (in the sense 'deceiving, deception'): via Old French from Latin illusio(n-), from illudere 'to mock', from in- 'against' + ludere 'play'.

  • The first sense recorded for illusion was ‘deception, attempt to fool’. It came via Old French from Latin illudere ‘to mock, ridicule, make sport of’, from in- ‘against’ and ludere ‘play’. The prime modern sense of ‘a false idea or belief’ dates from the late 18th century.

Words that rhyme with illusion

allusion, collusion, conclusion, confusion, contusion, delusion, diffusion, effusion, exclusion, extrusion, fusion, inclusion, interfusion, intrusion, obtrusion, occlusion, preclusion, profusion, prolusion, protrusion, reclusion, seclusion, suffusion, transfusion

For editors and proofreaders

Syllabification: il·lu·sion

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