noun
the day in 2001 when Arab suicide bombers hijacked United States airliners and used them as bombs
• Syn: ↑9/11, ↑September 11, ↑Sept. 11, ↑Sep 11
• Topics: ↑terrorism, ↑act of terrorism, ↑terrorist act
• Instance Hypernyms: ↑terrorist attack
Useful english dictionary. 2012.