DEFCON

noun

DEF·​CON ˈdef-ˌkän How to pronounce DEFCON (audio)
: any one of five levels of U.S. military defense readiness that are ranked from 5 to 1 according to the perceived threat to national security, with 1 indicating the highest level of perceived threat
It was determined that the secretary of Defense had the authority to declare DEFCON 3 on his authority.Stephen A. Cambone
sometimes used figuratively
Don't even mention the privatization of Social Security that will take Congress to DEFCON 1.Sam Allis

Examples of DEFCON in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
All those weird sensors in your brain that cry out for deliciousness are at DEFCON 1 all day. Claire Bugos, Verywell Health, 30 July 2024 Things nearly got even worse: after the Israelis recovered from their initial shock and began reversing Egyptian gains, Moscow threatened unilateral military measures, prompting the United States to go to DEFCON 3 and put its nuclear forces on worldwide alert. Gabriel Scheinmann, Foreign Affairs, 17 May 2015 Nevertheless, photos from reconnaissance flights showed the missile sites were near completion and U.S. armed forces were placed in DEFCON 2, the brink of war. David Goodhue, Miami Herald, 12 June 2024 Last year, for example, Scale provided an evaluation platform for a first-ever AI security challenge at the annual DEFCON hacker convention in Las Vegas, which tested AI models including OpenAI’s GPT-4 and was supported by the White House Office of Science, Technology, and Policy (OSTP). Sharon Goldman, Fortune, 21 May 2024 According to Politico, White House officials met with organizers of the hacker conference DEFCON in March and agreed at that time to support a public red-teaming exercise. IEEE Spectrum, 15 Mar. 2024 In the Mercedes, a collision notification call is placed via telematics as a DEFCON 2 measure before calling local emergency services. Jim Resnick, Ars Technica, 20 Jan. 2024 There also were no representatives from the fast-growing open-source A.I. ecosystem, most notably Hugging Face and Stability AI, both of which are also participating in the DEFCON 31 exercise. Jeremy Kahn, Fortune, 9 May 2023 Setting reasonable guardrails sounds like a great idea, but doing that will be cosmically difficult, particularly when one side is going DEFCON and the other is going public, in the stock market sense. Steven Levy, WIRED, 10 Mar. 2023

Word History

Etymology

defense condition

First Known Use

1959, in the meaning defined above

Time Traveler
The first known use of DEFCON was in 1959

Dictionary Entries Near DEFCON

Cite this Entry

“DEFCON.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/DEFCON. Accessed 16 Nov. 2024.

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