What it means
Basically means you can’t be bothered and you don’t care, like giving something the full British shrug. It’s blunt and a bit cheeky, often said about plans, chores, or drama that’s just not worth the hassle. Handy as a quick brush-off, but say it to someone’s face and they might get the hump.
Usage examples
"You coming to Kev’s motivational fun run at 7am? Not arsed, mate. I’m staying in, ordering a curry, and watching the rain kick off outside."
"I was gonna go to the gym but honestly I'm not arsed today."
Where it comes from
Built on "arse", the blunt British word for backside. To be not arsed is to lack even the bother of shifting it, the laziest shrug of indifference going, a close cousin of the fuller "can't be arsed".
Other ways to say it
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