What it means
Someone who's bonkers, unhinged, or so chaotic you don't know whether to laugh or hide your keys. Comes from nut meaning your head, like their brain's improvising. It's usually an insult, but it can be said affectionately for a mate who's fearless, reckless, and somehow always up for it. Use it lightly or you'll start a row.
Usage examples
"Jess rocked up to the charity do dressed as a traffic cone, then still did the bungee. Proper nutcase, but fair play, she raised two grand."
"My mate's a total nutcase, he jumped in the lake in January just because someone dared him."
"Driving like that in the fog, the man's an absolute nutcase, I had my eyes shut half the way."
Other ways to say it
Editors of this term
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