Related Clues:

• Not quite Mensa material
• Lower the lights
• Not the brightest bulb on the Christmas tree
• Sold-out show
• Thickly populated
• Bubbleheaded
• Darken
• Dense
• Not so smart
• Nebulous
• Thickly packed
• Make less bright
• Heavy, as fog
• Switch to low beam
• Rearranged needs?