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noun black·out \ˈblak-ˌau̇t\

Simple Definition of blackout

  • : a period when lights are kept off or are hidden from view to guard against enemy airplane attack in a war

  • : a period when lights are off because of an electrical power failure

  • : a sudden and temporary loss of consciousness, vision, or memory

Source: Merriam-Webster's Learner's Dictionary

Full Definition of blackout

  1. 1 a :  a turning off of the stage lighting to separate scenes in a play or end a play or skit; also :  a skit that ends with a blackout b :  a period of darkness enforced as a precaution against air raids c :  a period of darkness (as in a city) caused by a failure of electrical power

  2. 2 :  a transient dulling or loss of vision, consciousness, or memory <an alcoholic blackout>

  3. 3 a :  a wiping out :  obliteration b :  a blotting out by censorship :  suppression <a news blackout>

  4. 4 :  a usually temporary loss of a radio signal

  5. 5 :  the prohibition or restriction of the telecasting of a sports event

  6. 6 :  a time during which a special commercial offer (as of tickets) is not valid —usually used attributively <blackout dates>

Examples of blackout in a sentence

  1. the blackouts of World War II

  2. She keeps flashlights and candles handy in case of a blackout.

  3. He told his doctor he had been experiencing blackouts.


First Known Use of blackout


Rhymes with blackout

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BLACKOUT Defined for Kids


noun black·out \ˈblak-ˌau̇t\

Definition of blackout for Students

  1. 1 :  a period of darkness enforced as a protection against enemy attack by airplanes during a war

  2. 2 :  a period of darkness caused by power failure

  3. 3 :  a temporary loss of vision or consciousness

Medical Dictionary


noun black·out \ˈblak-ˌau̇t\

Medical Definition of blackout

  1. :  a transient dulling or loss of vision, consciousness, or memory <an alcoholic blackout>—compare grayout, redout

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