Octagon – A polygon with 8 sides
An octopus (octagon) has 8 tentacles (8 sides).
A regular convex octagon such as this has 8 sides of equal length and an internal angle of 135° between each side.
This is a concave octagon.
This shape may look a bit like a boat but is classified as an octagon due to it having 8 sides.
This may not look like an octagon but it has 8 sides, so it is an octagon.
This is an irregular octagon as the sides are not of equal length and the internal angles between the sides are not all the same.