9/11

American  

[nahyn-i-lev-uhn] / ˈnaɪn ɪˈlɛv ən /

Or 9-11

1. September 11, 2001: the day on which Islamic terrorists, believed to be part of the Al-Qaeda network, hijacked four commercial airplanes and crashed two of them into the World Trade Center in New York City and a third one into the Pentagon in Virginia: the fourth plane crashed into a field in rural Pennsylvania.

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9-11 Cultural  

1. See September 11 attacks.

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Etymology

Origin of 9/11

First recorded in 2000–05

Example Sentences

They have refused to do the basic job of paying the security personnel who are required to show up at airports nationwide to keep the public safe from another 9/11.

From The Wall Street Journal

Shortly after the 9/11 terrorist attacks, Fulop quit his job as a Goldman Sachs trader to join the Marines and deploy to Iraq.

From The Wall Street Journal

George W. Bush tapped him to lead the FBI shortly before 9/11.

From The Wall Street Journal

Security has been tighter at the Oscars every year since 9/11.

From Los Angeles Times

Six days after 9/11, George W. Bush visited the Islamic Center of Washington and declared “Islam is peace.”

From Salon