noun
- A nine-sided polygon. .
WordNet 3.0 © 2006 by Princeton University
| APA | WordNet. (2010). nonagon. Retrieved September 20, 2026, from http://smartdefine.org/nonagon/definitions/1244811 |
| Chicago | WordNet. 2010. "nonagon" http://smartdefine.org/nonagon/definitions/1244811 (accessed September 20, 2026). |
| Harvard | WordNet 2010, nonagon, Smart Define, viewed 20 September, 2026, <http://smartdefine.org/nonagon/definitions/1244811>. |
| MLA | WordNet. "nonagon" 23 October 2010. Web. 20 September 2026. <http://smartdefine.org/nonagon/definitions/1244811> |