What it means
Means completely exhausted and asleep, the kind where you could miss a fire alarm and still be dribbling on the cushion. Often after a mad shift, a heavy session, or just being properly knackered. Zonked also gets used for being wiped out or a bit medicated, but most of the time it just means out cold.
Usage examples
"He was zonked out on the sofa, telly blaring, still holding his kebab. I shouted his name twice and he didn’t even twitch."
"The kids were zonked out in the back seat before we even left the car park, two minutes and lights out."
Where it comes from
To be zonked out is to be utterly drained, flat out and dead to the world, usually slumped on the sofa or fast asleep mid-afternoon. The zonk is that heavy thud of total tiredness, often after a big day, a heavy meal or one too many late nights. Lights on, nobody home, in the most restful possible way.
Other ways to say it
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