\ˈa-ˌtȯl, -ˌtäl, -ˌtōl, ˈā- \

Definition of atoll 

: a coral island consisting of a reef surrounding a lagoon

Illustration of atoll

Illustration of atoll

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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.

Examples of atoll in a Sentence

Recent Examples on the Web

British physicist working for British intelligence goes undercover on a coral atoll in the Pacific to investigate a plot to steal a top secret weapon. Alessandra Stanley, New York Times, "In Praise of Alistair MacLean and the Male Romance," 13 Feb. 2018 On the direction of the U.S. Department of Defense, which maintains a military base in the Marshall Islands, Storlazzi's team was tasked with modeling how wave-driven flooding would impact the atoll of Roi-Namur. Michael Greshko, National Geographic, "Within Decades, Floods May Render Many Islands Uninhabitable," 25 Apr. 2018 Tahiti is one of the Society Islands, which is part of French Polynesia, made up of 118 islands and atolls. Catharine Hamm,, "Head for Tahiti on Air Tahiti Nui for $875 round trip from LAX," 2 Mar. 2018 In the 1960s, the few Chaggosians in the archipelago were relocated to make way for an American military base on Diego Garcia, the largest of the atolls. Jason Daley, Smithsonian, "Coral Reefs Need Fewer Rats and More Bird Poo," 12 July 2018 As the music plays, audiences are surrounded by projections of 3D imagery of coral reef from remote Pacific atolls. Cliff Kapono,, "UC San Diego composer uses the sounds of the sea to inspire conservation," 2 July 2018 Over the next decade some 250 submarines are expected to enter service in Asia—about half the total expected world-wide—as nations including Australia and Japan seek to counter China’s militarization of atolls in South China Sea. Rob Taylor, WSJ, "Australia’s $26 Billion Warship Deal Goes to Britain’s BAE," 28 June 2018 The Brando has also built and gifted an eco-station to the Tetiaroa Society, the nonprofit organization established to lead the scientific and cultural mission to protect the atoll and to inspire sustainable interdependence. Jill K. Robinson,, "Going green: Can we travel the world without killing the planet?," 21 June 2018 Small atolls and seamounts northwest of the Main Hawaiian Islands are also believed to have been formed by the hot spot. Audrey Mcavoy, Fox News, "Hawaii has 5 other active volcanoes in addition to Kilauea," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'atoll.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of atoll

1625, in the meaning defined above

History and Etymology for atoll

Divehi (Indo-Aryan language of the Maldive Islands) atolu

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Last Updated

11 Oct 2018

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The first known use of atoll was in 1625

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English Language Learners Definition of atoll

: an island that is made of coral and shaped like a ring


\ˈa-ˌtȯl, -ˌtäl\

Kids Definition of atoll

: a ring-shaped coral island consisting of a coral reef surrounding a lagoon

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full of whispering sounds

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