atoll

• 环状珊瑚礁、岛屿或岛链，环绕着潟湖，通常见于温暖的海洋水域。

A ring-shaped coral reef, island, or chain of islands that encloses a lagoon, typically found in warm ocean waters.

1. Ring-shaped coral reef islandB2formal

   A ring-shaped coral reef, island, or series of islets that encircle a lagoon partially or completely.

   环礁

   • The Maldives is a country made up of many atolls.
   • Divers explored the coral reefs surrounding the atoll.
   • The atoll's lagoon was calm and crystal clear.

   同义词coral reefreef