lose your marbles

lose (one's) marbles

To be or become mentally deficient, incompetent, or deranged; to become of unsound mind. My poor grandmother started losing her marbles after she had a stroke. I've been so sleep deprived lately that it feels like I've lost my marbles!
See also: lose, marble

lose your marbles

INFORMAL
If you lose your marbles, you become crazy. At 83 I haven't lost my marbles and my memory is, thank God, as clear as it ever was. People are talking about him as if he's lost his marbles. Note: You can also say that someone has all their marbles, meaning that they are not crazy. He's in his eighties but he clearly still has all his marbles.
See also: lose, marble

lose your marbles

go insane; become irrational or senile. informal
Marbles as a term for ‘a person's mental faculties’ probably originated as early 20th-century American slang. The underlying reference is apparently to the children's game played with multicoloured glass balls.
1998 Spectator At least, that is how I recall the event, but I am losing my marbles.
See also: lose, marble

lose your ˈmarbles

(informal) become crazy or mentally confused: They say the old man has lost his marbles because of the strange things he’s been saying, but I’m not so sure.
See also: lose, marble
References in periodicals archive ?
Robotnik's Mean Bean Machine, Columns III and Lose Your Marbles.
where it employs 130 people, SegaSoft is the award-winning publisher of popular CD-ROMs, including Cosmopolitan Virtual Makeover, Grossology and Lose Your Marbles, among others.
Lose Your Marbles offers hours of habit-forming, shameless fun for any PC user looking for a break.
The object of Lose Your Marbles is simple: Get rid of your marbles before your opponent does.
Lose Your Marbles offers multiple levels, bonus rounds, a practice mode and one- or two-player modes to entertain the leisure player and challenge hard-core gamers.
We expect to escort a few Lose Your Marbles addicts out of the booth at the end of the day," says Lori Von Rueden, SegaSoft director of marketing.
System requirements for Lose Your Marbles include an IBM PC or compatible with 60 MHz processor, CD-ROM, Windows(r) 95, 1 mg video card, 8 mg RAM and DirectX 3.
Lose Your Marbles is the second in a series of inexpensive, interactive Desktop Distractions from SegaSoft.