mess around with (someone)

1. to have sex with someone other than your husband, wife, or usual sexual partner.

She found out that her husband was messing around with her best friend.

2. to treat someone badly.

He was always messing around with her, and she was right to leave him.

• be born with a silver spoon in mouth
• be born with a silver spoon in your mouth
• be bound and determined
• be brain dead
• be bright and breezy
• be bright-eyed and bushy-tailed
• be broad in the beam
• be brother's keeper
• be brought to account
• be built like a brick shithouse
• be built like a tank
• be built on sand
• be bulging at the seams
• be bumping along the bottom
• be burnt to a crisp
• be bursting at the seams
• be called to account
• be carried out feet first
• be carved in stone
• be cast in a different mould
• be cast in the same mould
• be caught in the crossfire
• be caught in the middle
• send out something
• send packing