geometry

English

Etymology

From Middle English gemetry, geometrie, from Old French geometrie (modern French géométrie), from Latin geōmetria, from Ancient Greek γεωμετρία (geōmetría, “geometry, land-survey”), from γεωμέτρης (geōmétrēs, “land measurer”), from γῆ (gê, “earth, land, country”) + -μετρία (-metría, “measurement”), from μέτρον (métron, “a measure”). By surface analysis, geo- +‎ -metry. Doublet of gematria.

Pronunciation

• (Received Pronunciation) IPA^(key): /d͡ʒiːˈɒm.ɪ.tɹi/, /ˈd͡ʒɒm.ɪ.tɹi/
• (General American) IPA^(key): /d͡ʒiˈɑ.mə.tɹi/

  • Audio (US)

    (file)

• (General Australian) IPA^(key): /d͡ʒiːˈɔm.ə.tɹi/

Noun

geometry (countable and uncountable, plural geometries)

1. (mathematics, uncountable) The branch of mathematics dealing with spatial relationships.
   • 1925, René Descartes, “The Geometry of Rene Descartes”, in David Eugene Smith, Marcia Latham, transl., , Cosimo Classics, published 2007, page 2:

     ANY problem in geometry can easily be reduced to such terms that a knowledge of the lengths of certain straight lines is sufficient for its construction.

2. (mathematics, often qualified in combination, countable) A mathematical system that deals with spatial relationships and that is built on a particular set of axioms; a subbranch of geometry which deals with such a system or systems.
   • 1975 , Eugene F. Krause, Taxicab Geometry, 1986, Dover, page 64,

     Entire new geometries are also suggested by real-world cities.

   • 2004, Judith Cederberg, A Course in Modern Geometries, Springer, page 1:

     Finite geometries were developed in the late nineteenth century, in part to demonstrate and test the axiomatic properties of completeness, consistency, and independence.

   • 2006, Mark Wagner, The Geometries of Visual Space, Lawrence Erlbaum Associates, page ix:

     Previous theorists have often tried to test whether visual space is best described by a small set of traditional geometries, such as the Euclidean geometry most of us studied in High School or the hyperbolic and spherical geometries introduced by 19^th-century mathematicians.

3. (countable) The observed or specified spatial attributes of an object, etc.
   • 1990, M. E. Cage, D. Y. Yu, G. Marullo Reedtz, “Observation and an Explanation of Breakdown of the Quantum Hall Effect”, in Journal of Research of the National Institute of Standards and Technology, volume 95, number 1:

     The inset of figure 1 shows the geometry of the samples. They are 4.6 mm long and 0.4 mm wide.

   • 2003, Matt Welsh, Running Linux, page 74:

     Also, certain SCSI controllers need to be told where to find drive geometry in order for Linux to recognize the layout of your drive.

   • 2018 March 14, Roger Penrose, “'Mind over matter': Stephen Hawking – obituary”, in The Guardian:

     He was extremely highly regarded, in view of his many greatly impressive, sometimes revolutionary, contributions to the understanding of the physics and the geometry of the universe.

4. (algebraic geometry, countable) A mathematical object comprising representations of a space and of its spatial relationships.

Holonyms

• mathematics

Derived terms

Related terms

• gematria
• geometer
• geometric
• geometrical

Translations

See also

• topology

References

Further reading

• geometry on Wikipedia.Wikipedia
• “geometry”, in The Century Dictionary , New York, N.Y.: The Century Co., 1911, →OCLC.
• “geometry”, in OneLook Dictionary Search.
• Geometry on Encyclopedia of Mathematics.
• Geometry on Wolfram MathWorld.
• Geometry on Wikibooks.