not all there
be not all there
1. To not be mentally sound; to be insane. A: "Look at that guy talking to himself on the corner." B: "I reckon he's not all there."
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.
not all there
Fig. not mentally adequate; crazy or silly. Sometimes I think you're not all there. Be nice to Sally. She's not all there.
not all there
not in full possession of your mental faculties. informalnot all there
mod. crazy; stupid acting. You can’t depend on Paul for much help. He’s really not all there.