Related Clues:

• Theer or heer, e.g.
• Proofreader's catch
• Glitch on the page
• Keyboard goof
• Reason to backspace, perhaps
• Ink stain
• Secretarial goof
• Newspaper goof
• Manuscript blunder
• Keyboard mishap
• Blurry spot
• Dirt stain
• Dark mark
• Eraser mark
• Minks for monks, maybe