| a reef composed mainly of coral and other organic matter of which parts have solidified into limestone. |
| coral reef n. An erosion-resistant marine ridge or mound consisting chiefly of compacted coral together with algal material and biochemically deposited magnesium and calcium carbonates. |
A formation, at or near the surface of tropical waters, formed by skeletal deposits of corals, a form of sea life.
Note: Coral reefs form a protective environment for a wide variety of marine animals.
Note: Atolls — ring-shaped islands that nearly or entirely enclose a lagoon — are coral reefs.
Note: The largest coral reef is the Great Barrier Reef of Australia.
Note: Coral reefs are very sensitive to chemical pollution and changes in temperature and are considered to be in danger from environmental stress.
