1. when a child misbehaves, e.g. "The kids were playing up all morning, it was a nightmare!" 2. when something fails to function properly. e.g. "The battery in my phone is playing up" 3. when a part of your body causes you pain or doesn't function properly "my back's been playing up again" 4. to exaggerate a problem - make it seem more serious than it really is "Papers are playing up the fighting between Bernie Sanders and Hilary Clinton" More information and a transcript (soon) here: http://wp.me/P4IuUx-65h