Answer: dimwit

AnswerCrossword Clue
DIMWIT

Blockhead

DIMWIT

Lamebrain

DIMWIT

Doofus

DIMWIT
Nincompoop
DIMWIT
Knucklehead
DIMWITNo Einstein, this one
DIMWITNumbskull
DIMWITNot-too-bright sort
DIMWITDumbbell
DIMWITStupid one
DIMWITMeathead
DIMWITChucklehead
DIMWITNot the brightest bulb on the Christmas tree
DIMWITIdiot
DIMWITNumskull
DIMWITNot the brightest crayon in the box