An Etymological Dictionary of Astronomy and Astrophysics

A triangle having two sides equal.

Etymology (EN): From L.L. isosceles, from Gk. isoskeles “with equal legs; that can be divided into two equal parts,” from isos “equal, identical,” → iso-, + skelos “leg.”

Etymology (PE): Sebar, → triangle, do-pahlu-baraabar, from do, → two, pahlu, → side, barâbar, → equal.