9/11
noun /ˌnaɪn ɪˈlevn/
/ˌnaɪn ɪˈlevn/
- the abbreviation for the date September 11, 2001, when terrorists flew planes into the Twin Towers in New York, the Pentagon in Washington, D.C., and a field in Pennsylvania, killing thousands of peopleCulturePeople in the US write dates in the form of the month followed by the day, whereas in Britain the month follows the day. However, the US form is used in both countries to refer to the day of these attacks. The abbreviation often appears in phrases describing people or things connected with them, for example 9/11 families (= families affected by the attacks), the 9/11 Commission, the post-9/11 world.