A shape with 8 sides is an octagon.
There is no specific name for such a shape.
A shape with eight straight sides is called on octagon. There is not another specific name, but you could call it the more generic name: polygon.
a eight sided shape is called a octagon.
A shape with 7 sides is a heptagon
A shape with three sides is a triangle.
An Octagon.
Octagon
An octagon.
you call a two dimensional shape with six sides a hexagon
An octagon has 8 sides and 8 angles.
The shape is an octagon.