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Synonyms

imaginary

American  
[ih-maj-uh-ner-ee] / ɪˈmædʒ əˌnɛr i /

adjective

  1. existing only in the imagination or fancy; not real; fancied.

    an imaginary illness; the imaginary animals in the stories of Dr. Seuss.

    Synonyms:
    illusory, baseless, chimerical, shadowy, visionary, fanciful
    Antonyms:
    real

noun

imaginaries plural
  1. Mathematics. imaginary number.

imaginary British  
/ -dʒɪnrɪ, ɪˈmædʒɪnərɪ /

adjective

  1. existing in the imagination; unreal; illusory

  2. maths involving or containing imaginary numbers. The imaginary part of a complex number, z, is usually written Im z

"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

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Etymology

Origin of imaginary

1350–1400; Middle English < Latin imāginārius, equivalent to imāgin-, (stem of imāgō ) image + -ārius -ary

Explanation

Anything imaginary is not real: it only exists in someone's head. We hate to ruin your day, but unicorns are imaginary. Our imagination allows us to think of anything we want, and things that only exist in our minds are imaginary. Many children have imaginary friends: people they talk to who aren't real. Mythological beings like dragons, Zeus, and Thor are imaginary. A fantasy about marrying a movie star is probably imaginary, because that isn't likely to happen.

Keep Reading on Vocabulary.com

Vocabulary lists containing imaginary

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:

For decades, quantum mechanics has relied on complex numbers, which combine a real component with an imaginary component.

From Science Daily Jul. 13, 2026

Actors search for emotional truth in imaginary lives.

From Los Angeles Times Jul. 13, 2026

In the corner, Lionel Messi was moving almost in slow motion, his arms methodically swinging against an imaginary tide.

From BBC Jun. 27, 2026

Sometimes the text will address a bird as “you,” as if to participate in an imaginary conversation.

From The Wall Street Journal Jun. 12, 2026

His regard for her was quite imaginary; and the possibility of her deserving her mother’s reproach prevented his feeling any regret.

From "Pride and Prejudice" by Jane Austen

“We have to, as artists, find the courage to disrupt convention, practice the spreading of hope and cultivate new stories and imaginaries that challenge divisive binaries.”

From Seattle Times Oct. 24, 2023

“I love how he weaves in the African oceanic imaginaries, the long durée of African historical inter-relationships with the world, and with itself,” Owuor added.

From Los Angeles Times Oct. 18, 2021

These were found in the anharmonic ratio, a device leading to the liberation of synthetic geometry from metrical relations, and in involution, which yielded rigorous definitions of imaginaries.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various

Poncelet throughout his work makes continual use of the foregoing theories of imaginaries and infinity, and also of the before-mentioned theory of reciprocal polars.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" by Various

The theorem is here referred to partly on account of its bearing on the theory of imaginaries in geometry.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" by Various