Meaning & use

isosceles

adjective·Academic

Describing a triangle that has exactly two sides of equal length and two equal angles.

See it in a sentence

The students measured the isosceles triangle to confirm that two of its sides matched.

An isosceles roof truss balances evenly because both slanted sides are the same length.

A note on using this word

An isosceles triangle differs from an equilateral triangle, which has all three sides equal, and a scalene triangle, which has none equal.

Words with a similar meaning

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