spherical triangle

American  

noun

Geometry.

1. a triangle formed by arcs of great circles of a sphere.

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spherical triangle British  

noun

1. a closed geometric figure formed on the surface of a sphere that is bounded by arcs of three great circles

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Etymology

Origin of spherical triangle

First recorded in 1575–85

Example Sentences

Spending long nights in antiaircraft positions watching the skies, he imagined spherical triangles drawn across the sky and worked out their geometry.

From New York Times

Containing or having two right angles; as, a birectangular spherical triangle.

From Project Gutenberg

Thus we might have a spherical triangle that is concave, with its base 359°, and its other two sides each 90°, the sum of the sides being 539°.

From Project Gutenberg

The sum of the interior angles of a spherical triangle is always greater than two right angles, and increases with the area.

From Project Gutenberg

The clerestory windows are spherical triangles enclosing three circles with quatrefoil cusps; the form of these windows is somewhat rare, but similar windows are to be seen at Westminster, Hereford, Carlisle, and York.

From Project Gutenberg