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a·toll

(ătôl′, -ŏl′, ātôl′, ātŏl′)

An island or chain of islets connected by a coral reef that nearly or entirely encloses a lagoon.

[Dhivehi atholhu; probably akin to Sinhalese ätul, interior (from the interior lagoon), probably from Sanskrit *antala-, interior, variant of antara-; see en in the Appendix of Indo-European roots.]

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atoll

An atoll is created as a coral reef builds up around an eroding volcanic island.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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