barrier reef

American  

noun

1. a reef of coral running roughly parallel to the shore and separated from it by a wide, deep lagoon.

---

barrier reef British  

noun

1. a long narrow coral reef near and lying parallel to the shore, separated from it by deep water See Great Barrier Reef

---

barrier reef Scientific  

1. A long, narrow ridge of coral that runs parallel to the mainland and is separated from it by a deep lagoon.

2. Compare atoll fringing reef

---

Etymology

Origin of barrier reef

First recorded in 1795–1805

Example Sentences

See Examples For:

barrier reef

The “underwater city” of a barrier reef bustles with activity, with vibrantly patterned fish darting busily between corals and sea sponges.

From The Wall Street Journal ● May 22, 2026

Today, the 32-year-old is not just enabling others to experience the underwater world; he is playing a key role in helping protect the planet's third-largest barrier reef from the deadliest coral sickness ever recorded.

From BBC ● Dec. 9, 2023

This string of tropical islands is home to the only living coral barrier reef in the continental US, along with many animals found nowhere else in the world.

From Science Daily ● Oct. 9, 2023

As ocean temperatures rise to historic levels for July — a buoy in the shallow Florida Bay recently registered 101.1 degrees at the surface — corals are bleaching along Florida’s fragile 350-mile-long barrier reef.

From Los Angeles Times ● Aug. 1, 2023

The big front doors stood open to the sea, where a mile away the breakers tossed and tumbled on the barrier reef.

From Wild Justice: Stories of the South Seas by Osbourne, Lloyd