What it means
Prat is a classic, fairly mild insult for someone being a bit of an idiot, usually through cluelessness rather than malice. It’s less nuclear than wanker, more the kind of thing you mutter with a sigh when someone should know better. Fun fact, it originally meant your backside, so you’re basically calling them an arse with manners.
Usage examples
"Some prat wedged himself in the Tube doors with a massive suitcase, then acted shocked when everyone started tutting and squeezing past."
"Don't be such a prat, you've put the batteries in the wrong way round again."
Where it comes from
Started life as old thieves cant for the backside, then slid into meaning a fool, roughly the same journey "arse" took. These days it is a soft, almost affectionate jab, and to "prat about" means to mess around doing nothing useful.
Other ways to say it
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