The difference in one's appearance between their best and worst. Its often used to comment on a girl's looks after she dresses up, puts on make-up etc, versus her in her everyday state. Can also be used to comment on guys, alhough less common
1. Did you see hot how Kate was looking last night, she has so much disparity- shes normally average!
2. Lauren has no disparity, she always looks the same
Prolly means My dick your mouth.