Related Clues:

• Stupid
• ''As --- as the day ...''
• Virtuous
• One way to be struck
• Unintelligent
• ''No kidding!''
• 'It's the truth!'
• 'It's true!'
• Dimwitted
• True-blue
• 'For real?'
• On the square
• Dim
• Straight up
• Upstanding