404

[ fawr-oh-fawr, fohr-oh-fohr ]
/ ˈfɔr oʊˈfɔr, ˈfoʊr oʊˈfoʊr /

noun

Also called 404 error. Computers. 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.
Slang. a person who is stupid or uninformed.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for 404

404

/ (ˌfɔːəʊˈfɔː) /

noun

slang a stupid or ineffectual person

Word Origin for 404

C21: from the Internet error message `404 Not Found'
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