mentally inept
Retarted, stupid or incapable
When John got the question wrong we thought he was mentally inept
mentally inept
The smart way of saying mentally retarded, defective, special, etc.
Garrison: Obama is a pretty good president!
Harrison: You're mentally inept
Harrison: You're mentally inept
Mentally inept
mentally stupid, foolish, and especially dumb, in the head
This teacher is so mentally inept, how is he still here?