equilateral

[ ee-kwuh-lat-er-uhl, ek-wuh- ]

adjective

1. having all the sides equal:

   an equilateral triangle.

noun

1. a figure having all its sides equal.
2. a side equivalent, or equal, to others.

equilateral

/ ˌiːkwɪˈlætərəl /

adjective

1. having all sides of equal length

   an equilateral triangle

noun

1. a geometric figure having all its sides of equal length
2. a side that is equal in length to other sides

equilateral

/ ē′kwə-lăt′ər-əl /

1. Having all sides of equal length, as a triangle that is neither scalene nor isosceles.

Derived Forms

• ˌequiˈlaterally, adverb

Other Words From

• equi·later·al·ly adverb
• none·qui·later·al adjective
• none·qui·later·al·ly adverb
• sube·qui·later·al adjective
• une·qui·later·al adjective
• une·qui·later·al·ly adverb

Word History and Origins

Origin of equilateral¹

From the Late Latin word aequilaterālis, dating back to 1560–70. See equi-, lateral

Example Sentences

One way was to have three of them all on the same face, forming an equilateral triangular base.

From FiveThirtyEight

At this point, you could think of the crystal as two equilateral triangles connected by a common edge.

From FiveThirtyEight

So if five of the edges had the same length — meaning the sixth edge was the only one with a potentially different length — that meant the two faces not straddled by this sixth edge were equilateral triangles.

From FiveThirtyEight

For example, if you had three pennies in your pocket, then you could buy three strings that were each 1 cm long and form an equilateral triangle.

From FiveThirtyEight

Three of them were flat on the ground, with their corners touching and enclosing an equilateral triangle.

From FiveThirtyEight

Equilateral can be read as a parable of the ways we blind ourselves through vanity, love, and greed.

From The Daily Beast

The Khedive of Egypt persuades himself that the success of the equilateral will silence his local political rivals.

From The Daily Beast

A third game was called trign, and was played by three persons, stationed at the angles of an equilateral triangle.

From Project Gutenberg

I mean of course by the relative pointed, the entire group of which the equilateral arch is the representative.

From Project Gutenberg

It is built in the figure of an equilateral triangle, having one of its angles pointing towards the sea.

From Project Gutenberg

This consists of three plane mirrors so arranged that a cross-section of the three forms an equilateral triangle.

From Project Gutenberg

My legs and thighs first formed an obtuse angle, afterwards an equilateral angle, and at length, an acute one.

From Project Gutenberg

Related Words

• rectangular