pons asinorum

American  

[as-uh-nawr-uhm, -nohr-] / ˌæs əˈnɔr əm, -ˈnoʊr- /

noun

Geometry.

1. a geometric proposition that if a triangle has two of its sides equal, the angles opposite these sides are also equal: so named from the difficulty experienced by beginners in mastering it. Euclid, 1:5.

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pons asinorum British  

/ ˌæsɪˈnɔːrəm /

noun

1. the geometric proposition that the angles opposite the two equal sides of an isosceles triangle are equal

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Etymology

Origin of pons asinorum

First recorded in 1745–55; from Latin pōns asinōrum “bridge of asses”

Example Sentences

A month or two ago you blundered on "pons asinorum."

From Time Magazine Archive

The pons asinorum is free to all comers and even the eternal triangle's points are true for either hemisphere.

From Time Magazine Archive

The famous pons asinorum had become the bridge between two worlds.

From The Wolf's Long Howl by Waterloo, Stanley

The bridge of stability is therefore not even a pons asinorum.

From Landmarks of Scientific Socialism "Anti-Duehring" by Engels, Friedrich

I soon saw that the young girl who had been chosen as the star pupil to wrestle with the pons asinorum was giving an exhibition of memorizing and not of mathematical reasoning.

From Mobilizing Woman-Power by Blatch, Harriot Stanton