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 aim of his logic is represented as having been the devising of rules for the discovery of syllogistic middle terms; this system for aiding slow-witted persons became known as the pons asinorum.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" by Various

This proposition has long been called the pons asinorum, or bridge of asses, but no one knows where or when the name arose.

From The Teaching of Geometry by Smith, David Eugene

In twenty minutes' time, the donkey was climbing up a long flight of stairs to Caper's studio, as seriously as if he were crossing the pons asinorum.

From The Continental Monthly, Vol. 1, No. 5, May, 1862 Devoted To Literature And National Policy by Various