dead zone

American  

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.

3. a period or place where there is little activity or excitement.

   A dead zone for home sales is November and December.

---

dead zone British  

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 prosper

   a dead zone for cinemas

---

Etymology

Origin of dead zone

First recorded in 1875–80, for an earlier sense

Example Sentences

Steven Roberts, a local taxi driver, described Tenby as a signal "dead zone" and said it was impacting bookings and payments.

From BBC • May 3, 2026

Once a reliably lucrative box office market, China has become a dead zone for many Hollywood films popular in the rest of the world.

From The Wall Street Journal • Jan. 25, 2026

When the algae decays, it consumes oxygen, making the lake hypoxic — a dead zone without oxygen to support marine life.

From Los Angeles Times • Aug. 6, 2024

The same phosphorus that fertilizes the thriving agriculture of the Midwest is also responsible for a vast "dead zone" in the Gulf of Mexico near the Mississippi Delta.

From Science Daily • Feb. 7, 2024

The nitrogen runoff has creating a “hypoxic,” or dead, zone in the Gulf that is as big as the state of New Jersey—and still growing.

From "The Omnivore's Dilemma" by Michael Pollan