What it means
To lose your marbles means to go a bit mad or start acting like your common sense has done a runner. Your marbles are your sanity, so losing them paints a nice picture of your thoughts clattering off in every direction. Usually said half joking, half worried, when someone’s making truly baffling choices or having a wobble.
Usage examples
"He blew his last fifty quid on a novelty sword and reckons he’s starting a dojo in the lounge. Dad: you’ve lost your marbles."
"Have you lost your marbles, you cannot drive to Scotland and back in one day just for a sandwich."
"Gran reckons the council have lost their marbles building a roundabout where the duck pond used to be."
Other ways to say it
Editors of this term
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