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

INFORMALIf 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