What it means
A nutter is someone acting mad, unhinged or just wildly chaotic. It can be a proper insult if you mean they’re genuinely not right, but most of the time it’s said with a smirk about a reckless mate who’ll jump in first and think later. Mildly affectionate, mildly alarming, always entertaining.
Usage examples
"He necked his pint, climbed the fence and tried to high-five the bouncer. Absolute nutter, mate, but you’ve got to respect the confidence."
"Some nutter was out jogging in shorts in the middle of the snowstorm."
Where it comes from
From "nut", long slang for the head and, by extension, for being a bit off it. A nutter is someone whose nut seems to have come loose, used both for the genuinely unhinged and, more fondly, the cheerfully reckless mate.
Other ways to say it
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