noun
- The day in 2001 when Arab suicide bombers hijacked United States airliners and used them as bombs.
- synonyms: 9/11, September 11, Sept. 11, Sep 11
WordNet 3.0 © 2006 by Princeton University
| APA | WordNet. (2010). 9-11. Retrieved September 21, 2026, from http://smartdefine.org/9-11/definitions/1254187 |
| Chicago | WordNet. 2010. "9-11" http://smartdefine.org/9-11/definitions/1254187 (accessed September 21, 2026). |
| Harvard | WordNet 2010, 9-11, Smart Define, viewed 21 September, 2026, <http://smartdefine.org/9-11/definitions/1254187>. |
| MLA | WordNet. "9-11" 23 October 2010. Web. 21 September 2026. <http://smartdefine.org/9-11/definitions/1254187> |