irregularity

noun

• An instance of being irregular.
• The state or condition of being irregular, or the extent to which something is irregular.
• An object or event that is not regular or ordinary.

  "an irregularity of surface"

• A violation of rules.

  "An investigation of the irregularities in the company's accounts uncovered a large-scale fraud."

• Irregular bowel movement (e.g. diarrhea or constipation).