What it means
A zero tolerance policy means the rule's got no wiggle room at all. You break it once and that's enough, punishment lands, no excuses, no one-off pass, no little mercy coupon. People use it for schools, workplaces, clubs, policing, or anywhere trying to come off ultra strict. A lot of the time it's said with a bit of eye-roll energy because it can feel proper heavy-handed.
Usage examples
"Our school’s gone zero tolerance on phones, mate: one buzz in your pocket and they’ll nab it till Friday, no excuses."
"The new manager went zero tolerance on lateness from the first Monday, even a six-minute delay gets logged, and the morning queue at the bus stop has grown noticeably."
"Mum has gone zero tolerance on screens after seven for the kids, the change has been wild, suddenly they read books and ask board game questions like in the eighties."
"The office has gone zero tolerance on swearing in customer calls, so now everyone's muting themselves to have a little rage whisper."
"They're doing zero tolerance on fake IDs at the club tonight, so if your cousin turns up with that dodgy laminated relic, he's finished at the door."
Where it comes from
The phrase got real traction in the US in the 1980s through policing and crime policy talk, especially around cracking down on minor offences with no exceptions. By the 1990s it had spread into schools, workplaces, and public policy, turning into the standard label for strict rules with no slack.
