mess around

mess around (third-person singular simple present messes around, present participle messing around, simple past and past participle messed around)

1. (informal) To fiddle idly.

   The kids sat there messing around with leaves and blades of grass because they were bored.

   These guys don't mess around! They finished the whole job in ten minutes.

2. (informal) To joke, kid, or play.

   Hey, don't take it personally. I was only messing around.

   Don't mess around with electricity if you don't understand it.

3. (informal) To have a sexual relationship, especially one which is non-commital.
   • 2016, Lucy Dacus (lyrics and music), “Troublemaker Doppelgänger”, in No Burden, Matador Records:

     She grew up as the pretty young thing / Let them look up her skirt on the backyard swing, oh no / And Daddy told you to stay indoors / And I can understand how a girl gets bored / Too old to play and too young to mess around

   Rumor has it that he's messing around with his secretary.

• (all senses): mess about
• (fiddle idly): faff about (British, idiomatic), dick around (American, vulgar), waste time

• mess with