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Synonyms

atoll

American  
[at-awl, -ol, -ohl, uh-tawl, uh-tol, uh-tohl] / ˈæt ɔl, -ɒl, -oʊl, əˈtɔl, əˈtɒl, əˈtoʊl /

noun

  1. a ring-shaped coral reef or a string of closely spaced small coral islands, enclosing or nearly enclosing a shallow lagoon.

atoll British  
/ əˈtɒl, ˈætɒl /

noun

  1. a circular coral reef or string of coral islands surrounding a lagoon

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of atoll

First recorded in 1615–25; earlier atollon, from French: a word used in early descriptions of the Maldive Island atolls; said to be Divehi ( Indo-Aryan language of the Maldives) atoḷu

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

When the Marines headed toward the beach on the Tarawa atoll in 1943, things didn’t go well.

From The Wall Street Journal • Mar. 4, 2026

Under a contentious deal inked with Australia this year, the island nation will provide 30-year visas for up to 350 immigrants -- many convicted of serious crimes -- for resettlement on the barren atoll.

From Barron's • Nov. 25, 2025

The crew was astonished at the beauty of the atoll, a postcard photo of South Seas paradise.

From Slate • Jul. 22, 2025

“The Aviator and the Showman” leaves no doubt about Earhart’s disappearance: She misjudged her gasoline reserves, panicked and crashed near tiny Howland atoll.

From Los Angeles Times • Jul. 11, 2025

Both of those atoll types present problems to human settlers, because they consist entirely of limestone without other stones, have only very thin soil, and lack permanent fresh water.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.