isosceles triangle

noun

plural isosceles triangles
: a triangle in which two sides have the same length

Examples of isosceles triangle in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The trio will appear to form a broad isosceles triangle with Venus marking the vertex angle, while Aldebaran and the moon form the base of the triangle. — Joe Rao, Space.com, 18 July 2025 The only obstacle is that this hunk is her best friend Lady Danbury’s (Adjoa Andoh) estranged brother, forming an odd isosceles triangle of Regency relations. — Devon Ivie, Vulture, 14 June 2024

Word History

First Known Use

1570, in the meaning defined above

Time Traveler
The first known use of isosceles triangle was in 1570

Rhymes for isosceles triangle

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Browse Nearby Words

isosceles trapezoid
isosceles triangle
isosebacic acid
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Cite this Entry

“Isosceles triangle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isosceles%20triangle. Accessed 31 Aug. 2026.

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