# Euclidean

### or Eu·clid·i·an

[yoo-klid-ee-uh n]

- of or relating to Euclid, or adopting his postulates.

## Origin of Euclidean^{}

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

## Examples from the Web for euclidean

### Historical Examples

#### He acted as if he had demonstrated a Euclidean proposition flawlessly.

Occasion for DisasterGordon Randall Garrett

#### He constructed every one of his later speeches on the plan of a Euclidean solution.

The Poets' LincolnVarious

#### In elementary geometry, however, the Euclidean idea is still held.

The Teaching of GeometryDavid Eugene Smith

#### He returned the proof, saying that he could not accept any of it as elucidating the exact area of a circle, or as Euclidean.

The Life and Letters of Lewis CarrollStuart Dodgson Collingwood

#### The proof itself is borrowed, with slight alterations, from Cuthbertson's "Euclidean Geometry."

The Life and Letters of Lewis CarrollStuart Dodgson Collingwood

## Word Origin and History for euclidean

# Euclidean

Online Etymology Dictionary, © 2010 Douglas Harper

# Euclidean

[yōō-klĭd′ē-ən]

- Relating to geometry of plane figures based on the five postulates (axioms) of Euclid, involving the derivation of theorems from those postulates. The five postulates are: 1. Any two points can be joined by a straight line. 2. Any straight line segment can be extended indefinitely in a straight line. 3. Given any straight line segment, a circle can be drawn having the line segment as radius and an endpoint as center. 4. All right angles are congruent. 5. (Also called the parallel postulate.) If two lines are drawn that intersect a third in such a way that the sum of inner angles on one side is less than the sum of two right triangles, then the two lines will intersect each other on that side if the lines are extended far enough. Compare non-Euclidean.

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