be not all/quite there

be not all there

1. To not be mentally sound. A: "Look at that guy talking to himself on the corner." B: "I reckon he's not all there." My grandfather hasn't been all there for a number of years, which has really had a negative impact on how the kids interact with him.
2. To not be very bright or intelligent; to be dimwitted. Jim's a nice guy, but with some of the foolish things he does, I think he's not all there. My aunt likes to act like she's not all there sometimes, but she's actually incredibly sharp.
See also: all, not, there
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

be not all/quite ˈthere

(informal) think slowly because of low intelligence, illness, drugs, etc: Are you sure he’s all there? OPPOSITE: all there
See also: all, not, quite, there
Farlex Partner Idioms Dictionary © Farlex 2017
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