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

By means of his third and fourth propositions he is now able to prove the pons asinorum, that the angles at the base of an isosceles triangle are equal.

From The Teaching of Geometry by Smith, David Eugene

But we will not now traverse the ethical pons asinorum of necessity—the most simple and evident of mortal truths, and the most darkened, tortured, and belabored by moral teachers.

From Ancient and Modern Celebrated Freethinkers Reprinted From an English Work, Entitled "Half-Hours With The Freethinkers." by Bradlaugh, Charles

This axiom evidently expresses the symmetry of perpendicularity, and is the essence of the famous pons asinorum expressed as an axiom.

From The Concept of Nature The Tarner Lectures Delivered in Trinity College, November 1919 by Whitehead, Alfred North