from The American Heritage® Dictionary of the English Language, 4th Edition

  • adj. Mathematics Having two equal sides: an isosceles triangle.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • adj. Having two sides of equal length, used especially of an isosceles triangle or isosceles trapezoid.

from the GNU version of the Collaborative International Dictionary of English

  • adj. Having two legs or sides that are equal; -- said of a triangle.

from The Century Dictionary and Cyclopedia

  • Having two legs or sides equal: as, an isosceles triangle.
  • n. A genus of cerambycid longicorn beetles.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adj. (of a triangle) having two sides of equal length


Late Latin īsoscelēs, from Greek īsoskelēs : īso-, iso- + skelos, leg.
(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek ἰσοσκελής, from ἴσος (isos, "equal") + σκέλος (skelos, "leg"); another word of the same root is scalene. (Wiktionary)


  • Two men compete for the favors of a bored girl who wishes the hell with both of them — a spare sexual isosceles which is nicely symbolized in clean, stripped images of sail, sky, and water which group and re-group in triangles and trapeziums of gray and white as the boatload of trouble skims trimly across the lake.

    3 1/2

  • For example, if one knows that the angles of all triangles are equal to two right angles, one knows in a sense-potentially-that the isosceles’ angles also are equal to two right angles, even if one does not know that the isosceles is a triangle; but to grasp this posterior proposition is by no means to know the commensurate universal either potentially or actually.

    Posterior Analytics

  • Well, almost – we were taught trapezoids and isosceles triangles.

    À la carte, à la, Al

  • Yet, in 5 minutes, it explained to me what an isosceles trapezoidal arrangement is.

    À la carte, à la, Al

  • Its head is an isosceles triangle, with the tip being the right angle.

    The Bug on the Glass « Unknowing

  • The production is aided by Jon Gaw's unusually functional and evocative set that situates the characters in what amounts to the base of a isosceles triangle whose tip extends indefinitely into a far-off vanishing point, suggesting both a going-nowhere claustrophobia as well as the prospect of infinite hope.

    James Scarborough: Little Shop of Horrors, STAGEStheatre, Fullerton

  • I learned Weaver, and I can do it, but even though it is more of a martial artist's stance, it's still a conscious choice and isosceles isn't.

    Ready on the Left? Ready on the Right?

  • LE pistol training is shifting back to the isosceles stance from the Weaver as a result of looking at what actually happens in shootings.

    Ready on the Left? Ready on the Right?

  • I've been working for about 4 years to shift to the isosceles...

    Ready on the Left? Ready on the Right?

  • The most common stances for two-handed pistol shooting are isosceles and Weaver, If you have time, you get into the one you like.

    Ready on the Left? Ready on the Right?

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