isosceles

[ ahy-sos-uh-leez ]

adjective

1. (of a straight-sided plane figure) having two sides equal:

   an isosceles triangle; an isosceles trapezoid.

isosceles

/ aɪˈsɒsɪˌliːz /

adjective

1. (of a triangle) having two sides of equal length
2. (of a trapezium) having the two nonparallel sides of equal length

isosceles

/ ī-sŏs′ə-lēz′ /

1. Of or relating to a geometric figure having at least two sides of equal length.

Word History and Origins

Origin of isosceles¹

1545–55; < Late Latin < Greek isoskelḗs with equal legs, equivalent to iso- iso- + skél ( os ) leg + -ēs adj. suffix

Word History and Origins

Origin of isosceles¹

C16: from Late Latin, from Greek isoskelēs, from iso- + skelos leg

Example Sentences

A sort of isosceles triangle is formed, which will eventually collapse.

From Los Angeles Times

Something about isosceles triangles that I learned the year before at Iqra.

From Literature

Evenly spaced branches reached out from a trunk twisted into gentle contrapposto, its clusters of spring green foliage suggesting the outline of an isosceles triangle.

From New York Times

The first warm evenings brought the summer triangle, a brilliant isosceles made up of the stars Vega, Deneb and Altair, to the eastern edge of my yard.

From Washington Post

That’s when an equilateral triangle becomes an isosceles, often with one person isolated at the farthest point.

From Washington Post