What it means
Batty means crazy, daft, or a bit unhinged, usually said with a grin rather than full-on concern. If someone's gone batty, they've started acting irrational, doing wild impulse stuff, or chatting nonsense. It's proper everyday British speech, the sort of word your auntie uses when your mate makes yet another terrible decision.
Usage examples
"Gaz bought three hundred quid trainers for the school run, then queued an hour for a limited drop. Mum said he's gone batty."
"Gran has gone proper batty in retirement, knits jumpers for the neighbour's dog, names her tomato plants and writes Christmas cards to the woman on the weather report."
"My mate's a bit batty after three days at the festival, keeps offering strangers tea bags and calling everyone Steve, even the dog of the lad in the next tent."
Where it comes from
From bats in the belfry, the Victorian image of small flying creatures rattling around in the head where calmer thoughts should be. The phrase shortened over the decades until batty alone carried the daftness, no church tower required and no bell rope swinging in the back of the brain.
Other ways to say it
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