be missing some of (one's) marbles(redirected from be missing some of their marbles)
be missing some of (one's) marbles
To be mentally deficient, incompetent, or deranged; to be of unsound mind. My poor grandmother is missing some of her marbles after her stroke. I've been so sleep deprived lately that it feels like I'm missing some of my marbles!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.