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a. An erroneous perception of reality: Mirrors gave the illusion of spaciousness.
b. An erroneous concept or belief: The notion that money can buy happiness is an illusion.
2. The condition of being deceived by a false perception or belief: spent months flailing about in illusion.
3. Something that is erroneously perceived or construed: The animal in the shadows turned out to be an illusion.
4. A fine transparent net fabric, used for dresses or trimmings.

[Middle English illusioun, from Old French, from Late Latin illūsiō, illūsiōn-, from Latin, a mocking, irony, from illūsus, past participle of illūdere, to mock : in-, against; see in-2 + lūdere, to play; see leid- in Indo-European roots.]

il·lu′sion·al, il·lu′sion·ar′y (-zhə-nĕr′ē) adj.
il·lu′sion·less adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.illusionary - marked by or producing illusion; "illusionary stage effects"
unreal - lacking in reality or substance or genuineness; not corresponding to acknowledged facts or criteria; "ghosts and other unreal entities"; "unreal propaganda serving as news"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in classic literature ?
Freedom from the domination of the great tradition could only be found by seeking new subjects, and such freedom was really only illusionary, since romantic subjects alone are suitable for epic treatment.
It must interfere quickly to restore the peoples' rights, instead of making statement now and then about illusionary solutions that are not related to reality.
On cue, hero Emrn Hashmi did an illusionary levitation trick at the do.
In an interview with Israel's Channel 2 television on Friday, Olmert said that Netanyahu spent approximately $3 billion on "illusionary security escapades that have not been implemented and will not be implemented", according to Reuters.
"Scoring illusionary victories does not serve the national interest," he added.
And what I did on the rainbow, which is illusionary more colourful, I asked the children to paint, I mean drawing basically," said Bala Subramaniam, a Bangalore artist.
The argument being put forward in favour of paying bank bosses astronomical bonuses is that these millionaires will take their illusionary talents elsewhere.
BAGHDAD / Aswat al-Iraq: The Iraqi Parliament has convened on Sunday to discuss the issue of the so-called "illusionary" contacts with Electricity Minister Raad Shallal who was recently sacked because of it, according to a Parliament media source.
* SIR - House owners may be leaping with joy at the illusionary price rise of home but this is a disaster for those who have lost their jobs, others forced to take wage and salary cuts, for we have seen repossession rising again.
The complexity of Al Jawharah's external faE*ade creates reflective panels which disperse and refract light, creating an illusionary effect.
But you have to be sure that you are looking at a true net profit not an illusionary one."
Perfection is an illusionary quality we always search for and seldom find.