hump da bump means: This is a dance that many females enjoy, but men hate because of the tightening of their pants. This is a move girls use to seduce men and get them to believe that they want to go to bed with her. The girl is just trying to get her pants wet and wants to move on. You won’t sleep with her, so make sure you have your jock strap ready before you hit the floor. (in Community Dictionary, added by Enrique García)