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

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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

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Other Word Forms

• imaginarily adverb
• imaginariness noun
• nonimaginarily adverb
• nonimaginarilyness noun
• nonimaginariness noun
• nonimaginary adjective
• preimaginary adjective
• unimaginary adjective

Etymology

Origin of imaginary

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

Example Sentences

Soon after, he transformed his childhood treehouse into his own imaginary rocket ship.

From BBC • Apr. 2, 2026

We’re going to be playing videogames using thought interaction on screens projected from eyewear to an imaginary field of view.

From The Wall Street Journal • Mar. 23, 2026

Joseph weaves together an imaginary “Transatlantic Biennial” and W.E.B.

From Los Angeles Times • Mar. 4, 2026

"I tell my children imaginary stories. I try to make the stories motivating and uplifting," she said, such as tales of a new home with separate rooms and beds.

From Barron's • Mar. 3, 2026

Occasionally, he’d split his mental gymnastics, leaving his imaginary board to swing a fantasy baseball bat and knock an invisible ball into the left-field stands of the Ebbets Field in his mind.

From "Endgame" by Frank Brady

Related Words

• abstract
• fanciful
• fantastic
• fictional
• hypothetical
• imagined
• theoretical
• unreal
• whimsical