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Syllabification: e·qui·lat·er·al
Pronunciation: /ˌēkwəˈladərəl
, ˌekwəˈladərəl

Definition of equilateral in English:


Having all its sides of the same length: an equilateral triangle
More example sentences
  • An equilateral triangle of side length one is called a unit triangle.
  • This is constructed by dividing a line into three equal parts and replacing the middle segment by the other two sides of an equilateral triangle constructed on the middle segment.
  • Then divide it into three equal pieces, and replace the middle piece with the other two sides of the equilateral triangle that has this middle piece as its base.


late 16th century: from French équilateral or late Latin aequilateralis, from aequilaterus 'equal-sided' (based on Latin latus, later- 'side').

Definition of equilateral in:

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