What is a six-sided figure called?

A 6-sided polygon is called a hexagon. A polygon is any closed figure with 3 or more sides and angles. Every polygon from 3 to 20 has a name. Polygons with 30, 40, 50, 60, 70, 80, 90 and 100 sides have names, as well.

Polygons with 3 to 12 sides, excluding 9 and 11, have commonly used names. A 3-sided polygon is a triangle, and a 4-sided polygon is a quadrilateral. A 5-sided polygon is a pentagon, and a polygon with 7 sides is a heptagon. A polygon with 8 sides is known as an octagon, and a 10-sided polygon is a decagon, while a 12-sided polygon is a dodecagon. The names of polygons with more than 12 sides exist but are less commonly used.