1 B1 idiomatic neutral
To faint or lose consciousness suddenly.
"She blacked out from the heat and woke up on the floor of the stadium."
inseparable
black out
B1 neutral separable transitive/intransitive
To lose consciousness or memory; to extinguish all lights; to censor by covering with black; or to suffer a total power failure.
In plain English
To suddenly faint or lose memory, OR for all the lights to go out completely.
What does "black out" mean?
4 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B1 idiomatic informal
To experience a period of memory loss, often due to alcohol or trauma.
"He drank so much at the party that he blacked out and couldn't remember getting home."
inseparable
3 B2 neutral
To cover or delete text, images, or information so that it cannot be read, usually for censorship or security.
"Several lines of the report had been blacked out before it was released to the public."
separable
4 B1 neutral
To extinguish or cut off all lights or electrical power in an area.
"The city was blacked out for six hours after the storm damaged the power lines."
“
London was blacked out and German aircraft droned overhead.
— Winston Churchill, The Second World War (historical reference to WWII blackouts)
separable
Literal vs figurative
Words literally mean
To turn something completely black — extinguishing light or visibility.
Actually means
To suddenly faint or lose memory, OR for all the lights to go out completely.
Usage tip
One of the most versatile phrasal verbs with this particle. The medical/psychological sense (fainting, memory loss) is very common in everyday speech. The censorship sense (blacking out text) is common in news and government contexts. The electrical sense (power blackout) is widely used. Often becomes the noun 'blackout.'
Words that pair with "black out"
Natural word combinations native speakers use most often.
lights power text windows memory stage
How to conjugate "black out"
The five tense forms you'll use most often.
Base
black out
I/you/we/they
3rd person
blacks out
he/she/it
Past simple
blacked out
yesterday
Past participle
blacked out
have + pp
-ing form
blacking out
continuous
Hear "black out" in the wild
Listen to native speakers using "black out" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
Jump to every phrasal verb built on the same verb, particle, or level.