A ring-shaped reef, island, or chain of islands formed by coral. is called atoll
It covers a body of water called a lagoon
An island is any type of land that rises above the water on all four sides of the surrounding water. Whereas atolls are made up of a chain of islands made up of a ring-shaped island.
What is the difference between an island and an atoll?
Kiritimati Atoll is the largest atoll in the world with an area of 150 square miles (388 square km). It is in the west-central Pacific Ocean.
What is the largest atoll in the world?
The small country of the Maldives in the center of the Indian Ocean is made up of approximately 1,200 tiny coral islands grouped into 26 atolls.