noun
1.
a place or a period of time in which nothing happens :
The town is a cultural dead zone.
2.
an area which separates two places, groups of people, etc. :
The UN is trying to maintain a dead zone between the warring groups.
3.
a place where a mobile phone / cellphone does not work because no signal can be received
4.
( biology ) an area of water in which animals cannot live because there is not enough oxygen