noun

DEFCON

DEHF-kon

DEFCON (noun) means a numbered scale used by the US military to indicate its level of alert readiness, from DEFCON 5 (normal) to DEFCON 1 (maximum readiness). Example: “The base was placed on DEFCON 3 during the standoff.”

noun

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."

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."

Frequently asked questions

What does “DEFCON” mean?

The word “DEFCON” means a numbered scale used by the US military to indicate its level of alert readiness, from DEFCON 5 (normal) to DEFCON 1 (maximum readiness).

How do you pronounce “DEFCON”?

“DEFCON” is pronounced DEHF-kon (/ˈdɛfkɑn/ in IPA).

How do you use “DEFCON” in a sentence?

Here is “DEFCON” used in a sentence: “The base was placed on DEFCON 3 during the standoff.”

What part of speech is “DEFCON”?

“DEFCON” is a noun.

How many meanings does “DEFCON” have?

“DEFCON” has 2 distinct senses listed in this dictionary. The most common is: a numbered scale used by the US military to indicate its level of alert readiness, from DEFCON 5 (normal) to DEFCON 1 (maximum readiness).