black out phrasal verb ( see also ↑ black )
1 . to become ↑ unconscious SYN faint , pass out :
For a few seconds, he thought he was going to black out.
2 . black something ↔ out to put a dark mark over something so that it cannot be seen:
The censors had blacked out several words.
3 . black something ↔ out to hide or turn off all the lights in a town or city, especially during war
⇨ blackout