to behave in a silly and annoying way, especially instead of doing sth useful; to treat sb in an unfair and annoying way, especially by changing your mind a lot or not doing what you said you would
to behave in a silly and annoying way, especially instead of doing sth useful
Will you stop messing around and get on with some work?
to spend time doing sth for pleasure in a relaxed way
We spent the day messing around on the river.
mess sb about / aroundBritish
to treat sb in an unfair and annoying way, especially by changing your mind a lot or not doing what you said you would
Definitions from the Oxford Advanced Learner's Dictionary, 9th edition