Related Clues:

• Not the brightest bulb on the tree
• Hardly qualified to be a rocket scientist
• Numskull
• Doltish
• Stupid
• Thick as a brick
• Unintelligent
• Packed
• Cement-headed
• No rocket scientist
• Like a blockhead
• Dimwitted
• Short on sharpness
• Blockheaded
• Stupid person