Mess about Definition 1 of 3Pro Tip 1/3Lack of Purpose Reflects spending time without a clear goal, often in a leisurely way. He messes about with puzzles on lazy Sundays. Pro Tip 2/3Casual Activity Suggests informal, relaxed behavior with no serious intent. She loves messing about in the kitchen, trying new recipes. Pro Tip 3/3Time Filler May imply using the activity to pass time rather than for productivity. We just mess about with the app when we're bored.