Fool around (Short video)

The phrase of the day is: "Fool around"

• To engage in aimless recreation or frivolous time-wasting.
  [ --- If he would spend less time fooling around he would be able to get some work done. --- ]
  
• To joke about something. Often used in the negative to indicate absolute seriousness.
  [ --- Oh, come on, Tina, we're just fooling around. We didn't mean it. --- ]
  
• To have a casual sexual relationship with someone.
  [ --- Hey, don't fool around with the thermostat. It needs to stay at 68 degrees. --- ]