1. An area of water with insufficient oxygen to support most aquatic life, typically caused by excessive nutrient pollution
The Gulf of Mexico has a large dead zone due to agricultural runoff from the Mississippi River.
O Golfo do México tem uma grande zona morta devido ao escoamento agrícola do Rio Mississippi.
2. An area with no signal reception or coverage, particularly for mobile phones or radio
There is a dead zone in the basement where you cannot get cell phone reception.
Há uma zona morta no porão onde você não consegue recepção de telefone celular.
3. A region where a particular activity, service, or phenomenon does not occur or is not accessible
Rural areas are often dead zones for high-speed internet service.
Áreas rurais são frequentemente zonas mortas para serviço de internet de alta velocidade.