A more thorough explanation:

Definition: Irregular (adjective) means not following the usual rules or patterns. Examples:

• She has an irregular work schedule, sometimes working late into the night and other times starting early in the morning.
• The shape of the rock was irregular, with jagged edges and uneven surfaces.
• His attendance at school was irregular, often skipping classes without permission.

These examples illustrate how something can be irregular if it does not follow a set pattern or rule. In the first example, the work schedule is irregular because it does not follow a consistent pattern. In the second example, the shape of the rock is irregular because it does not have a smooth or uniform shape. In the third example, the student's attendance is irregular because it does not follow the school's rules for attendance.