What does "lights out" mean?

Alternative form of lights-out.

What is a synonym for "lights out"?

Common synonyms include: bear, dash off, dig out, flight, hasten off, head.

noun, verb

noun, verb ·Rare ·Advanced level

Noun

1
Alternative form of lights-out. alt-of, alternative
2
Unconsciousness. idiomatic
"There had been one almighty BANG and then it had been lights out."

Verb

1
third-person singular simple present indicative of light out form-of, indicative, present, singular, third-person

"There had been one almighty BANG and then it had been lights out."