In ice hockey, icing is an infraction that occurs when a player shoots, bats with the hand or stick, or deflects the puck over the center red line and the opposing teams red goal line, in that order, and the puck remains untouched without scoring a goal). The result of icing is a face-off in the defensive end of the team who sent the puck to begin with. The National Hockey League (NHL) introduced the icing rule in September 1937 to eliminate a common delaying tactic used by teams to protect a winning margin).

There are different types of icing, including touch icing, no-touch icing, and hybrid icing). In touch icing, play is stopped when the puck is touched by a defending player after crossing the goal line). In no-touch icing, play is stopped when the puck crosses the goal line without being touched by any player). Hybrid icing is a combination of touch and no-touch icing, where play is stopped for icing if the player on the opposing team reaches the faceoff dot first, instead of skating all the way across the goal line to touch the puck). This type of icing is intended to reduce the number of collisions along the boards during touch icing, while still allowing the team that iced the puck to get to it first to wave off the icing).

In the NHL, icing is a double-edged strategy because it can disrupt an offensive threat, pausing the flow and momentum of the attacking team or creating a pause in the action so the defensive team can get organized. For this reason, opposing NHL players race for the puck in a potential icing situation, because which team is likely to touch the puck first determines whether icing is called. An NHL rule passed in 2013 resulted in “hybrid icing,” where the linesman must determine which player will touch the puck first after it crosses the goal line. If the linesman judges that the defensive player will reach the puck first, icing is called; if the attacking player is in the lead, icing is not called and play continues.