1. A plane figure of eight sides and eight angles; a place with eight sides.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• octogon,
• octain,
• otagon,
• octogan,
• octagone,
• octigon,
• octagona,
• octagonn,
• oktagon,
• octroon,
• octoron,
• olcranon,
• Oktaroon,
• octogold,
• ocxygon,
• osteitoc,
• ocatagon,
• Attagon,
• Ottamon,
• ortagan

• octagonal.

The adjective form of the word "octagon" is "octagonal".

The plural of the "octagon" can be the "octagons".

The singular of the "octagon" can be the "octagon".