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.
See also: all, not, there
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

not all there

not in full possession of your mental faculties. informal
See also: all, not, there
Farlex Partner Idioms Dictionary

not all there

mod. crazy; stupid acting. You can’t depend on Paul for much help. He’s really not all there.
See also: all, not, there
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • not for a second
  • not for a minute
  • not for a moment
  • not for a instant
  • not for a/one minute/moment/second/instant
  • aint
  • ain't
  • hope not
  • (I) hope not
  • not by any means