What it means
Someone who's sparked out is completely out cold, either fast asleep or knocked senseless. You'll hear it after a big night, a grim shift, or a heavy hit, but day to day it's just someone conking out hard. If they're sparked out, alarms can scream and you could nick their last Hobnob and they still wouldn't budge.
Usage examples
"Got back from the club and he was sparked out on the settee, trainers on, telly shouting, cold chips balanced on his belly."
"He was sparked out on the sofa by nine, remote still in his hand and the telly blaring."
"Two minutes into the film the kids were sparked out, so we just sat in the quiet for once."
Where it comes from
It carries a knockout image, the lights going out all at once like a spark snuffed dead. Spark out has long meant flat-out unconscious, whether floored in a fight or simply collapsed after a brutal day, and once you are sparked out the world can carry on without you.
Other ways to say it
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