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plane geometry

American  

noun

Mathematics.
  1. the geometry of figures whose parts all lie in one plane.


plane geometry British  

noun

  1. the study of the properties of and relationships between plane curves, figures, etc

"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

plane geometry Scientific  
  1. The mathematical study of geometric figures whose parts lie in the same plane, such as polygons, circles, and lines.


plane geometry Cultural  
  1. The study of two-dimensional figures (figures that are confined to a plane).


Discover More

Plane geometry is one of the oldest branches of mathematics.

The Greek mathematician Euclid was the first to study plane geometry carefully. His book Elements was the standard plane geometry textbook for centuries.

Etymology

Origin of plane geometry

First recorded in 1740–50

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.

But their boxes, X-shapes and intersecting lines are as eternal as plane geometry.

From Washington Post • Jul. 2, 2015

By high-school plane geometry, the second circle will have four times the area of the first one.

From Time Magazine Archive

I have moved through arithmetic, through plane geometry and algebra, and now I am in calculus.

From Time Magazine Archive

In Western Air, Darby Bannard, 37, for instance, whips clouds of Dutch Boy house paints into a composition that contrasts Hollywood-pink plane geometry with cumulus skies.

From Time Magazine Archive

They’d have to use the plane geometry solution.

From "The Smartest Kid in the Universe" by Chris Grabenstein