What it means
Means you’ve lost the plot, gone a bit mad, or you’re acting wildly unreasonable or overexcited. It’s usually said as a teasing laugh when someone’s chatting absolute nonsense, but it can land as a proper put-down if you say it sharp. Handy for describing chaos in human form, from daft schemes to full-on melt-down energy.
Usage examples
"He reckons he’ll rebuild his mate’s Corsa with duct tape and a TikTok tutorial. Nah, he’s off his trolley, get him a cuppa and hide the spanners."
"He is off his trolley if he thinks I am driving four hours just to return a jumper that almost fits."
"The prices in that place are off their trolley, ten quid for a coffee and a tiny biscuit."
Where it comes from
Like off your rocker, the trolley here is the pole that connects a tram to its overhead wire. When the trolley slips off, the tram loses power and goes nowhere sensible. So to be off your trolley is to have come unhooked from good sense, to be talking complete nonsense.
Other ways to say it
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