equilateral

/ˌikwəˈlætərəl/

Other forms: equilaterally; equilaterals

A shape is equilateral if all the sides are the same length.

In geometry class, people learn about many shapes, such as triangles and squares. A square is equilateral, because all of its sides are the same length. A rhombus is also equilateral — its sides are also the same length. A triangle can be equilateral too, but not a scalene triangle, which has three sides of different lengths. The word equal should help you remember what equilateral means. You can also use it as a noun for an equilateral shape.

Definitions of equilateral

1. adjective

   having all sides or faces equal
   synonyms:

   equal

   having the same quantity, value, or measure as another
2. noun

   a figure whose sides are all equal
   type of:

   figure

   a combination of points and lines and planes that form a visible palpable shape