A player who is known for his defense and ability to "shut down" the opposing team's best offensive players.
Coaches will generally try and match these kind of players against the other team's top offensive lines to limit their scoring and frustrate them. These players are particualry important in the playoffs when long series make each and every game so crucial.
The best defensive forward is recognized each year by the National Hockey League - NHL with the Frank J. Selke award. Although these players are good defensively, they often still are able to contribute offensively at well, sometimes at key times in the playoffs it seems.