Definitions

from The American Heritage® Dictionary of the English Language, 4th Edition

  • adj. Having existence only in the imagination; unreal.
  • adj. Mathematics Of or being the coefficient of the imaginary unit in a complex number.
  • adj. Mathematics Of, involving, or being an imaginary number.
  • adj. Mathematics Involving only a complex number of which the real part is zero.
  • n. Mathematics An imaginary number.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • adj. existing only in the imagination
  • adj. of a number, having no real part; that part of a complex number which is a multiple of the square root of -1.

from the GNU version of the Collaborative International Dictionary of English

  • adj. Existing only in imagination or fancy; not real; fancied; visionary; ideal.
  • n. An imaginary expression or quantity.

from The Century Dictionary and Cyclopedia

  • Existing only in imagination or fancy; due to erroneous belief or conception; not real; baseless; fancied: opposed to actual.
  • In mathematics, unreal and feigned in accordance with the theory of imaginary quantities.
  • Synonyms Ideal, fanciful, fancied, visionary, unreal, shadowy, Utopian. Imaginary and imaginative are never synonymous: imaginary means existing only in the imagination; imaginative means possessed of or showing an active imagination.
  • n. In algebra, an imaginary expression or quantity.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adj. not based on fact; unreal
  • n. (mathematics) a number of the form a+bi where a and b are real numbers and i is the square root of -1

Etymologies

From Latin imāginārius ("relating to images, fancied"), from imāgo. (Wiktionary)

Examples

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Comments

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  • Well, it can be done; it just takes some imagination.

    The revery alone will do…

    March 2, 2009

  • And in fact the water would have to be a cuboidal volume sufficient to contain a hemisphere of Saturn, and that's got some gravity of its own (that's an emphatic 'some' . . . I wonder how you punctuate that?); not to mention the rigid material for the bath.

    March 2, 2009

  • That's really not such a great analogy if you think about it too much. I'm pretty sure the gravitational pull of Saturn would do some things do a bathtub full of water. The whole idea of floating doesn't make a lot of sense on this scale.

    March 2, 2009

  • Saturn is the only planet in our solar system that is less dense than water. If you could build an imaginary gigantic bathtub, Saturn would float in it.

    National Geographic, trying to palm it off on NASA. No, if you built an imaginary bath, the water would still all fall through. You need to imagine building a real gigantic bath for this one.

    February 23, 2009

  • The auto-generated definition is mathematically correct for a complex number, though in common usage it also applies to an imaginary number. The mathematically correct definition for imaginary number is:

    (n): (mathematics) a number of the form "bi" where "b" is a real number and i is the square root of -1

    May 13, 2008

  • Imagine a comment.

    November 5, 2007