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404

American  
[fawr-oh-fawr] / ˈfɔr oʊˈfɔr /

noun

  1. Also called 404 errorComputers. an error message sent by a web server to a browser when the user has typed an incorrect URL, tried to access a web page that is no longer available, or clicked on a broken link on a web page.

    They must have taken down their website;

    I keep getting that annoying “404 - File Not Found” message.

  2. Slang. a person who is stupid or uninformed.


404 British  
/ ˌfɔːəʊˈfɔː /

noun

  1. slang a stupid or ineffectual person

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of 404

First recorded in 1995–2000

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

I looked over at 404 reporter Rebecca Castillo in envy, knowing she was about to witness the Brooklyn outfit for the first time.

From Los Angeles Times Aug. 24, 2026

The symbol for that facility, 404 Media reported, was a sharp-toothed green dinosaur holding an open book.

From The Wall Street Journal Aug. 22, 2026

There are still transparency laws that apply to Flock databases, which is how 404 Media and other media outlets have discovered abuses of the technology.

From Salon Aug. 14, 2026

The Dow Jones Industrial Average fell 404 points, or 0.8%, while the S&P 500 was off 0.9%.

From Barron's Mar. 7, 2026

Mari did, but a 404 error popped up.

From "Boy 2.0" by Tracey Baptiste

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