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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

plural

imaginaries
  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

Other Word Forms

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.

“This first external raise is not just a milestone, but a validation of what’s been achieved in a single year,” said Logan Langberg, a partner at Imaginary Ventures.

From The Wall Street Journal • Jan. 20, 2026

“Goth” grew out of the book tour for Tolhurst’s 2016 memoir, “Cured: The Tale of Two Imaginary Boys,” which resembled a concert tour more than anything.

From Salon • Oct. 28, 2023

Imaginary numbers, when multiplied by themselves, produce a negative number.

From Scientific American • Apr. 24, 2023

But “Letter to an Imaginary Friend” is still here, awaiting the many more real friends it deserves.

From Los Angeles Times • Apr. 11, 2023

The left side had a column written by Mr. Donnelly, with the strange tide “Thoughts on an Imaginary Porcelain Plate.”

From "Tangerine" by Edward Bloor