dead zone

noun6

1. •
   A region where mobile phones do not operate because there is no base station or repeater nearby.

   • When you are in a dead zone, most of your call drops or your phone doesn't work at all. — 2005
2. •
   An area with no life.
3. •
   An area of the ocean where oxygen levels are too low to support life, especially as a result of pollution.
4. •
   A region within the player's viewpoint that is less sensitive to small movements, aiding accurate firing of weapons etc.
5. •
   The part of the field where a player is on their opponent's side of the field but kicking a field goal would probably be unsuccessful and punting the ball would not dramatically change field position.
6. •
   (historical) An area near a fortification that is relatively sheltered from defending fire because direct fire from other parts of the walls cannot be directed around a curved wall.