Sometimes called pons asinorum, which, perhaps more politely, says exactly the same thing in Latin.
Germans translate the Latin into Esels-briicke; French use pont aux lines, but they all refer to the fifth proposition of the first book of Euclid:
If a triangle has two of its sides equal, the angles opposite these sides are also equal.
The proof of this simple bridge-shaped figure is so difficult for those beginning the study of geometry as to give rise to the name, whatever the native country of the student.
