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1. verb To lose consciousness. My blood sugar dropped so low during the meeting that I blacked out and woke up on the floor.
2. verb To experience a period of time about which one does not remember anything, despite having been fully conscious at the time (as during a stressful or traumatic event.) It's like I blacked out during the interview—I don't remember anything I said!
3. verb To avoid thinking about or remembering something, often because it is stressful or traumatic. Many trauma victims try to black out the horrific things that have happened to them.
4. verb To prevent something from being broadcast or disseminated, usually in a specific geographic area. Ugh, the game must be blacked out tonight. Is it on any other channel? The dictator has blacked out news from the rest of the world.
5. verb To cover something (usually with black lines or blocks) so that it cannot be seen or read. Be sure to black out all the other names on this list before you put it in the employee's file. The newspaper blacked out part of the photograph.
6. noun An episode of unconsciousness. Often written as one word ("blackout"). My blood sugar dropped so low that I had a blackout during the meeting and woke up on the floor.
7. noun A period of literal darkness caused by the loss of electricity, as during a storm. Often written as one word ("blackout"). We read by candlelight to pass the time during the blackout.
8. adjective slang Extremely drunk, often to the eventual point of unconsciousness. Often written as one word ("blackout"). He was blackout last night, so I'm not surprised that he doesn't remember talking to you.
1. Lit. [for lights] to go out. Suddenly the lights blacked out. The power went dead and everything blacked out from the heat.
2. Fig. to pass out; to become unconscious. After I fell, I must have blacked out. I think I am going to black out.
black something out
1. Lit. to cut or turn out the lights or electric power. The lightning strike blacked the entire town out. The manager blacked out the whole building during the emergency to prevent an explosion.
2. Fig. to prevent the broadcast of a specific television or radio program in a specific area. Will they black the game out around here? They blacked out the basketball game in this area.
to stop being conscious I blacked out right after the accident.Related vocabulary: go blank
black out somethingalso black something out
1. to stop delivering or receiving electricity The power failure blacked out all of northern Illinois.
2. to keep from being broadcast or printed Tonight's game has been blacked out on local television so you have to buy tickets to see it. The local papers blacked out news of the disaster.
Etymology: based on the literal meaning of black something out (to keep something from being seen by covering it with black)
1. Obliterate with black, as in crossing out words on a page or print on a screen. For example, They have blacked out all the obscene words in the subtitles to make this movie suitable for youngsters . This usage may be derived from an earlier meaning, "to stain or defame," which dates from the 15th century (and probably alludes to "blackening" a person's reputation). [Mid-1800s]
2. Extinguish all lights. For example, The whole town was asleep, as blacked out as London during the war. In the early 1900s this expression alluded to the lights in a theater, but from about 1940 on it meant darkening an entire city to hide it from enemy bombers.
3. Lose consciousness, faint; also, experience a temporary loss of memory. For example, I couldn't remember a single note of the music; I blacked out completely, or The accused man claims he blacked out after his first drink. This usage is thought to have originated with pilots, who sometimes fainted briefly when pulling out of a power dive. It soon was transferred to other losses of consciousness or memory. [c. 1940]
1. To stop emitting light; go out: The traffic lights blacked out when the storm knocked down power lines.
2. To cause a failure of electrical power in some region: The strong winds blacked out much of the city.
3. To lose consciousness or memory temporarily: The patient felt very dizzy and blacked out for a few minutes.
4. To suppress some memory from the conscious mind: The refugees blacked out their wartime experiences.
5. To prohibit the broadcast or spread of something, especially by censorship: The government blacked out the news that was broadcast from enemy radio stations.