What is a 7-sided polygon called?

A polygon with seven sides is called a heptagon. A polygon is a closed geometric shape that has at least three sides and angles.

Polygons consist of adjoining line segments and are named based on how many sides they have. There are eight polygons that have been officially named...

• triangle: three sides
• quadrilateral: four sides
• pentagon: five sides
• hexagon: six sides
• heptagon: seven sides
• octagon: eight sides
• decagon: ten sides
• dodecagon: twelve sides

Other proposed names include "nonagon" for a nine-sided polygon and "undecagon" for an eleven-sided polygon.

The vertices of a polygon are the points where two sides meet. In an equiangular polygon, all of the angles are equal, while in an equilateral polygon, all of the sides have the same length. A regular polygon meets both conditions.