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 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 The Defense Ready Condition (DEFCON) system, to which West inaccurately refers, indicates situations of varying military severity, including nuclear, biological, or chemical threats; levels range from DEFCON 5 (normal) to DEFCON 1 (maximum readiness). PCMAG, 10 Oct. 2022 Able Archer 83 was a NATO exercise that year simulating conflict escalation with the Soviets that culminated in the U.S. military achieving DEFCON 1, the highest-level alert status indicating a coordinated nuclear attack is imminent or has already begun. Todd Spangler, Variety, 28 Sep. 2022 Readiness is raised to DEFCON 2, one step below that of nuclear war. Frank O’Brien, Ars Technica, 4 Jan. 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'DEFCON.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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.” Dictionary, Merriam-Webster, Accessed 25 May. 2024.

Last Updated: - Updated example sentences
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