isosceles

adjective

isos·​ce·​les ī-ˈsä-sə-ˌlēz 

-ˈsäs-ˌlēz

1

of a triangle : having two equal sides see triangle illustration

2

of a trapezoid : having the two nonparallel sides equal

Examples of isosceles in a Sentence

Recent Examples on the Web

Geographically, Richland, Hammonton, and Absecon don't form an isosceles triangle. — Phil Anastasia, Philly.com, 26 May 2017

Word History

Etymology

borrowed from Late Latin isoscelēs, borrowed from Greek isoskelḗs "having equal legs, (of a triangle) having two equal sides, (of numbers) divisible into equal parts, even," from iso- iso- + -skelēs, adjective derivative of skélos (neuter s-stem) "leg," going back to an Indo-European base *skel- "bent," whence also Armenian šeł "slanting, crooked"; with o-grade, Greek skoliós "bent, crooked, askew, devious"; perhaps with a velar extension Germanic *skelga-/*skelha-, whence Old English sceolh "oblique, wry," Old Frisian skilich "squinting," Old High German skelah "crooked, oblique," Old Icelandic skjalgr "wry, oblique"

Note: The Indo-European etymon is also conventionally compared with Latin scelus "misfortune resulting from the ill will of the gods, curse, wicked or accursed act, crime, villainy," a neuter s-stem that appears to match exactly Greek skélos, though if "crime" is secondarily developed from a sense "misfortune," with religious connotations, a connection with crookedness is less likely.

First Known Use

1551, in the meaning defined at sense 1

Phrases Containing isosceles

• isosceles triangle

Rhymes for isosceles

• actuaries
• analyses
• anopheles
• antitheses
• apostrophes
• appendices
• catalyses
• distributees
• examinees
• hypotheses
• interviewees
• paralyses

Kids Definition

isosceles

adjective

isos·​ce·​les ī-ˌsäs-(ə-)ˌlēz 

1

: being a triangle with two equal sides

2

: being a trapezoid whose two nonparallel sides are equal