go out like a light
Sleep strikes fast
To go out like a light is to fall asleep almost instantly, the way a light switches off: After that hike, I went out like a light.
The phrase can also mean to lose consciousness suddenly, whether from a blow, exhaustion, or anesthesia.
- pass outLose consciousness briefly
- dead to the worldDeeply, unrousably asleep
- fadeLose intensity gradually
- conk outCease functioning suddenly
- faintWeak and indistinct
black out · fall · swoon · fall asleep · fast asleep · collapse · knock out · crash out · hit the hay · hit the sack · sack out · sink · go to sleep · nod off · coma · sedation · slumber · doze