# Euclidean

### or Eu·clid·i·an

[ yoo-klid-ee-uhn ]
/ yuˈklɪd i ən /
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of or relating to Euclid, or adopting his postulates.
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## Origin ofEuclidean

1650–60; <Latin Euclīdē(us) of Euclid (<Greek Eukleídeios) + -an

## Words nearby Euclidean

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

## Scientific definitions for Euclidean

Euclidean
[ yōō-klĭdē-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.