"The block is a return with a flat paddle, i.e., perpendicular to the court. It is intended to use the force of the opponent's shot to rebound the ball back across the net at a slower pace.
The block and absorb is a return with a tilted paddle, i.e., the top of the paddle is tilted back slightly. The shot requires minimal forward and downward movement of one inch or less. The tilt of the paddle is intended to absorb some of the force while adding spin to the return." source Apple County blog.