dead zone

noun

1. Ecology. an area in a body of water, especially an ocean, having oxygen levels that are not adequate to support life: shellfish threatened by an annual dead zone in the Gulf of Mexico.
2. dead spot(def 1).
3. a period or place where there is little activity or excitement: A dead zone for home sales is November and December.

noun

1. an area of water that cannot support marine life, being virtually devoid of oxygen due to the presence of nitrates that stimulate algae growth
2. an area where a mobile phone does not receive a signal
3. any area where something does not exist or prospera dead zone for cinemas