DictionaryeuclideanFlat-space geometry
adjective

euclidean

yoo-KLID-ee-un/juˈklɪdiən/

Relating to classical geometry in flat space.

In Euclidean geometry, a triangle’s interior angles add up to 180 degrees.

A simple geometry construction on a flat white sheet: a prominent straight-sided right triangle with angle arcs and a right-angle square, beside a straightedge and transparent triangular set square.
Etymology

The adjective identifies geometry associated with Euclid and his axioms—the familiar framework for straight lines and angles. It is often contrasted with geometries that reject some of those axioms.

In context

Modern-Day Debate203:36
the railroad you see and at the limit they still converge so that literally just supports my point and it supports that you see it over uh flat you know euclidean plane geometry with uh hyperbolic non-euclidean visual space
FLAT EARTH DEBATE: Mark & David Vs Nathan & Witsit Gets It

More examples

  • Parallel lines never meet in Euclidean geometry.
  • The program calculates the Euclidean distance between two points.
  • A curved surface does not follow all the rules of Euclidean geometry.

Similar words

flat
Describes space without curvature, without explicitly naming Euclid’s geometry.