• (America) IPA: /ˈblæk.aʊt/
• (Canadian raising) IPA: /ˈblæk.ʌʊt/

blackout

1. A temporary loss of consciousness.

   Synonyms: blankout#Noun, faint#Noun, syncope

   Coordinate terms: grayout, greyout

2. A temporary loss of memory.

   Synonyms: blankout#Noun

3. A large-scale power failure, and resulting loss of electricity to consumers.

   Synonyms: power cut, outage

   Coordinate terms: brownout, dimout

4. An instance of censorship, especially a temporary one.

   media blackout

5. (internet) An intentional outage of a website or other online service, typically as a form of protest.

   the 2012 English Wikipedia blackout

6. (historical) The mandatory blocking of all light emanating from buildings, as well as outdoor and street lighting as a measure against aerial bombing or naval attack, as imposed during, e.g., World War II.
7. (attributive) The blocking out of as much light as possible.

   blackout blinds; blackout curtains

8. (slang, criminology, rare) A mass murder committed, usually in an urban area, to eliminate potential witnesses of a previous crime.

• French: blackout
• Italian: svenimento, mancamento, deliquio, lipotimia
• Portuguese: desmaio
• Russian: затемнение сознание
• Spanish: desmayo

• French: blackout, trou de mémoire
• German: Blackout, Erinnerungsverlust, Filmriss
• Portuguese: branca
• Russian: провал память
• Spanish: apagón

• French: blackout, coupure de courant
• German: Stromausfall, Blackout
• Portuguese: blecaute, apagão
• Russian: блэка́ут
• Spanish: apagón

• French: blackout
• Portuguese: blecaute
• Russian: затемне́ние
• Spanish: corte

blackout (blackouts, present participle blackouting; simple past and past participle blackouted)

1. (nonstandard)
   • 1941, Annual Report of the Boy Scouts of America: Letter from the Chief Scout Executive Transmitting the Annual Report of the Boy Scouts of America ... as Required by Federal Charter, Boy Scouts of America, page 37:

     Scouts assisted Mabel Smythe Building officials in blackouting windows.