Jabobhead
A Jabobhead is someone so clueless they think a donut is a type of sandwich.
My brother is a Jabobhead. He tried to build a treehouse and used glue instead of nails.
My friend is a Jabobhead. She thinks a donut is a sandwich and tried to eat it with a fork.
My math teacher is a Jabobhead. He added 2 + 2 and got 5. Then he cried.