I guess the dribble step is the step that is made BEFORE the dribble. The name is a bit confusing because it is not the foot that hits the floor while dribbling and that is what the name would suggest. It is the foot on the same side of the ball. I guess it is the step where the player decides either to continue his with the next dribble or to pull up. I would then call it the "dribble or pull-up decision step" The floatstep is the backleg when the ball is pocketed or in the hand of the dribbler. So it is the opposite foot of where the side of the ball is.