isosceles

[ ahy-sos-uh-leez ]

/ aɪˈsɒs əˌliz /

(of a straight-sided plane figure) having two sides equal: an isosceles triangle; an isosceles trapezoid.

Origin of isosceles

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

Each of these consists of a solid red triangle, isosceles or equilateral, with sides of 15-20 mm.

Mohave Pottery |Alfred L. Kroeber
Thus seated, they formed the figure of an isosceles triangle, with Ruth at the apex, the men at the angles of the base.

Other Things Being Equal |Emma Wolf
An isosceles or vacillating member is that to which two sides only are the same.

Punch, or the London Charivari, Vol. 1, October 9, 1841 |Various
They are held together by arched iron rods, as shown in the cut, so as to form the three angles of an isosceles triangle.

Scientific American Supplement, No. 483, April 4, 1885 |Various

Right things do come in so terribly askew, like good old Mr. Isosceles, sidling up the broad aisle of a Sunday!

We Girls: A Home Story |Mrs. A. D. T. Whitney

isosceles

/ (aɪˈsɒsɪˌliːz) /

(of a triangle) having two sides of equal length

(of a trapezium) having the two nonparallel sides of equal length

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

isosceles

[ ī-sŏs′ə-lēz′ ]

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