Word.ws English Dictionary

imaginary geometry

imaginary geometry noun: absolute geometry, an axiomatised geometry in which the parallel postulate is absent and not replaced by an alternative, and of which Euclidean geometry and some non-Euclidean geometries are subtypes.

Noun

imaginary geometry (uncountable)

  1. Absolute geometry, an axiomatised geometry in which the parallel postulate is absent and not replaced by an alternative, and of which Euclidean geometry and some non-Euclidean geometries are subtypes.
    • He liked talking about imaginary geometry, as a matter of pure amusement, to anyone interested in it. But at the same time he attached a serious import to it.1879, Frederick Pollock, Introduction, Part 1: Biographical, Leslie Stephen, Frederick Pollock (editors), William Kingdon Clifford, Lectures and Essays, Volume 1, Cambridge University Press, page 14
    • Claim 7. The Euclidean law of cosines holds for any infinitesimal triangle #92;triangleABC in imaginary geometry.2011, Seth Braver, Lobachevski Illuminated, Mathematical Association of America, page 188
    Synonyms:
    geometry with no parallel postulate

Synonyms of imaginary geometry

  • geometry with no parallel postulate

Origin of imaginary geometry

Calque of Russian мни́мая геометрия (mnímaja geometrija), coined by mathematician Nicolai Lobachevsky, probably influenced by мни́мое чи́сло (mnímoje číslo, “imaginary number”), although his precise reasoning is unknown.

Questions about imaginary geometry

What does imaginary geometry mean?
Imaginary geometry means absolute geometry, an axiomatised geometry in which the parallel postulate is absent and not replaced by an alternative, and of which Euclidean geometry and some non-Euclidean geometries are subtypes.
What part of speech is imaginary geometry?
Imaginary geometry is a noun.

Words near imaginary geometry in the dictionary

  1. imaginary
  2. imaginary axes
  3. imaginary axis
  4. imaginary friend
  5. imaginary friends
  6. imaginary geometry
  7. imaginary lat syndrome
  8. imaginary museum
  9. imaginary museums
  10. imaginary number
  11. imaginary numbers

Source and license

Adapted from Wiktionary: imaginary geometry (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Cite this entry: “imaginary geometry.” Word.ws, https://word.ws/imaginary_geometry. Based on Wiktionary, CC BY-SA 4.0.