parallel postulate

American  

noun

Geometry.

1. the axiom in Euclidean geometry that only one line can be drawn through a given point so that the line is parallel to a given line that does not contain the point.

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parallel postulate Scientific  

1. See under Euclidean

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Example Sentences

When I wrote about this idea with the parallel postulate, I imagined it as a stubborn wrinkle in a sheet.

From Scientific American

Geometry classes could explore the strange new worlds that arise from adopting different versions of Euclid’s infamous parallel postulate.

From Slate

In February, I wrote about Euclid’s parallel postulate, the black sheep of the big, happy family of definitions, postulates, and axioms that make up the foundations of Euclidean geometry.

From Scientific American

But what stood out to me the most was that while Carroll spent plenty of time on the parallel postulate, he made no mention in his book of non-Euclidean geometry. It’s not that the parallel postulate was not discussed; several sections include extensive explorations of the topic, and he included two related tables in his text.

From Salon

Here we have statements that are equivalent to the parallel postulate.

From Salon