A formal name for a batty boy
or a batty man
Usually used for jokes, such as filling in forms.
Taken from the Latin Batemonus, meaning Incompetent/lack of effort, It has come to mean a general slob who commits himself to a job but then never follows through.
E.G. Person 1 "My coach is a right Bateman!"
Person 2 : "For show! he doesn't even watch your matches, or whatever?!"