Related Clues:

• Campaigner's dirty trick
• Mark that might be left with greasy fingers
• Mascara mishap
• Greasy fingerprint, e.g
• Calligraphy mishap
• Cosmetic problem
• Do finger painting
• Lipstick flaw
• Mark from an old eraser
• Dirty mark; a libel
• Discredit material for examination that is on the slide
• Soil taken from dug-out in first Somme military engagement
• Dirty mark; aspersion
• Blur, blot
• Blot or daub