1. the quality or state of being impossible or difficult to read

Examples

• The doctor’s illegibility made it hard for the pharmacist to fill the prescription.
• Due to the illegibility of the handwriting, the letter was returned to sender.
• The illegibility of the ancient manuscript frustrated the researchers.
• Poor lighting contributed to the illegibility of the street signs.
• The illegibility of his signature caused problems at the bank.
• Water damage resulted in the complete illegibility of the document.