An "octagonal" shape has eight sides and eight angles. It is a type of polygon, which is a flat, two-dimensional figure with straight sides. The term comes from the Greek word "okto," meaning eight. Common examples of octagonal shapes include stop signs and certain types of tiles. In geometry, the interior angles of an octagon add up to 1,080 degrees, making each angle approximately 135 degrees in a regular octagon. Octagons can be found in various designs, architecture, and art, often used for their aesthetic appeal and structural properties. Examples include octagonal buildings and pavilions.