an attempt by a player, generally a forward, to regain possession of or disrupt an offensive players ability to control the puck as the play moves down ice

A responsibility of the forwards -- to cover an opponent as the play returns to the defensive zone.

To check an opponent while on the way back to the defensive zone.

Forwards in their offensive zone skate back quickly to their own defensive zone to protect their goal and keep the opponent from shooting.

This is when a player attempts to check or harass a person of the opposite team as they are reentering their defensive zone.

an attempt by a player, on his way back to his defensive zone, to regain the puck from the opposition by checking or harassing an opponent who has the puck.