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noun

DEFCON

DEHF-kon
noun
1
A numbered scale used by the US military to indicate its level of alert readiness, from DEFCON 5 (normal) to DEFCON 1 (maximum readiness).
"The base was placed on DEFCON 3 during the standoff."
2
Informally, one's own state of alarm or urgency, often used humorously.
"She hit DEFCON 1 the moment she saw the exam schedule."

How to Use DEFCON

Learner’s notes
Common mistake

Lower numbers mean higher alert — DEFCON 1 is the most severe, DEFCON 5 the calmest, which trips people up.

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Fill the Gap

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The base was placed on _____ 3 during the standoff.

Etymology

A blend of "defense" and "condition."

Definitions: FreeDict original editorial