Definition of DEFCON in English:


(also defcon)


  • Each of a series of five progressive levels of alert used by the US armed forces.

    ‘conventional and nuclear forces were moved to DEFCON 2’
    figurative ‘my stress levels have finally reached defcon 1’
    • ‘The Defense Department has these procedures - the "Defense Condition," or DEFCON, system.’
    • ‘On alert and tracking the storms, the National Hurricane Center is in full tilt mode, DEFCON 1, if you will.’
    • ‘During the 1962 missile crisis, when conventional and nuclear forces were moved to an even higher level of alert (DEFCON II), it was very difficult to control alerted forces.’
    • ‘They almost immediately rise to DEFCON 1 and start screaming themselves.’
    • ‘The phone rang and the Colonel's voice said, "Brown, we are at DEFCON 2, take your squadron immediately south to Omstead Air Force Base and set up for war until further notice."’
    • ‘Tolerance level for people in general is at DEFCON 1.’
    • ‘Cold wars have raged, mile after mile, between adult and offspring, and spouses have often moved to DEFCON I.’
    • ‘And whenever he pops up on oversea interviewers' radar, the hypocrisy meter was always touching the defcon 5.’
    • ‘The U.S. military has a similar system; DEFCON 1-5 corresponds to the five threat alerts levels: Green, Blue, Yellow, Orange, and Red.’
    • ‘On 22 October 1962 SAC responded by establishing Defense Condition Three (DEFCON III), and ordered B-52s on airborne alert.’
    • ‘In 1973, they did not understand the technical meaning or the operational consequences of the DEFCON III alert (U.S. forces were normally kept at DEFCON IV) and chose the alert in full confidence that it entailed no risks.’
    • ‘The difference is that the DEFCON system is tied to particular procedures; military units have specific actions they need to perform every time the DEFCON level goes up or down.’
    • ‘The Commander heightened his forces' alert and surveillance status and considered increasing readiness from the normal Defense Condition Four to DEFCON Three.’
    • ‘Something tells me Andrea Dworkin just went to DEFCON 2.’
    • ‘I'm at DEFCON - 3 with the washing machine actually.’


1950s: acronym from defence readiness condition.