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proper noun

September 11th 2001, the day when planes flown by terrorists destroyed the World Trade Center in New York and damaged the Pentagon, killing thousands of people


noun [countable]

an act of war or terrorism which is as serious as the terrorist attacks on September 11th 2001

'Mayor of London Boris Johnson unveiled a 9/11-themed artwork, made from the largest piece of the World Trade Centre outside of the United States, at Battersea Park, London, yesterday … The unveiling came on the same day that the cousin of a British-born hero of 9/11, who died in the Twin Towers, has spoken of his continuing sadness and pride at what his relative did that day.'

Yorkshire Post 7th September 2011

'Nations respond to their 9/11s … The dreaded follow-up to 9/11 hasn't come, at least in the United States. Al-Qaida-linked attacks instead rocked Madrid; London; … experts who have studied these other 9/11s say some offer important revelations, by comparison, about how America responded to its own.'

International Institute for Strategic Studies 6th September 2006

It's now a decade since Al-Qaeda terrorists hijacked four passenger planes and intentionally crashed into the Twin Towers of New York's World Trade Centre, causing the towers to collapse within two hours, and resulting in the deaths of thousands of people. Within hours of these tragic scenes hitting television screens across the world, this event became etched into the global consciousness by the description 9/11.

anyone who has made a journey by plane in the 10 years since 9/11 will know what an impact these events have had on our daily lives

On September 10th 2001, the digits 9/11 could be used as a simple date reference – 11th September or 9th November, depending on which side of the Atlantic you happened to be. Just twenty-four hours later however, both British and American English had made what has proved to be an irrevocable connection between this number sequence and the devastating events of that day. Spelt as 9/11, 9-11 or in full word form as nine eleven, in contemporary usage this combination of numbers can only mean one thing.

Anyone who has made a journey by plane in the 10 years since 9/11 will know what an impact these events have had on our daily lives. The entire concept of air travel has changed since 9/11 – from security checks to the contents of your luggage, nothing will ever be quite as relaxed as it was before. This is just one example of changes in attitudes and policies which mean that many of us inhabit a very different world to the one that existed previously. The cohort of young people who have grown up with these changes are now sometimes referred to as Generation 9/11, an expression used to describe the generation of people who were at school or college on September 11th 2001.

From real-world to lexical impact, there's also some evidence for the expression 9/11 further embedding itself in the language by occurring as a countable noun. Used in this way, 9/11 functions as a generic reference to any act of war or terrorism which is comparable in severity to the 2001 attacks, as illustrated in the second citation above.

Though undoubtedly rejected by many language users as being in bad taste, in slang there's also some evidence for use of 9/11 as a transitive verb, especially in full word form nine-eleven. If you nine-eleven something (or someone) you destroy it or cause serious damage (or injury) to it; so, for example, in a crash you might nine-eleven your car, or in a fight you could get nine-elevened. What remains to be seen is whether there will, over years to come, be a softening of the impact of the expression so that usages like these seem less offensive and become more widely accepted.

Background – 9/11

Voted 'Word of the Year' in 2001 by the American Dialect Society, 9/11 entered the US and international lexicon practically overnight, despite the different date conventions in Canada, Australia and Britain (where 9/11 would usually refer to the ninth day of the eleventh month, i.e. 9th November). Following the same model, the expression 7/7 appeared in 2005 as a knee-jerk reference to the terrorist bombings in central London, which, since happening on the seventh day of the seventh month, led to an expression appropriate to date systems on both sides of the Atlantic.

by Kerry Maxwell, author of Brave New Words

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This article was first published on 12th September 2011.

Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

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