Simple Definition of atoll
: an island that is made of coral and shaped like a ring
Full Definition of atoll
: a coral island consisting of a reef surrounding a lagoon
Did You Know?
If you are lucky enough to sail south and west of Sri Lanka in the Indian Ocean, you'll find the Maldives, a group of about 1,200 coral islands and sandbanks that form the Republic of Maldives. Many islands in that independent nation demonstrate the archetypal atoll, and geographers often use them to point out the characteristic features of such coral islands. Given how prevalent atolls are there, it isn't surprising that atoll comes from the name for that kind of island in Divehi, the official language of the Maldives.
Origin of atoll
Divehi (Indo-Aryan language of the Maldive Islands) atolu
First Known Use: 1625
ATOLL Defined for Kids
Definition of atoll for Students
: a ring-shaped coral island consisting of a coral reef surrounding a lagoon
Seen and Heard
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