island arc

American  

noun

1. a curved chain of islands, as the Aleutians or Antilles, usually convex toward the ocean and enclosing a deep-sea basin.

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island arc British  

noun

1. an arc-shaped chain of islands, such as the Aleutian Islands or the Japanese Islands, usually lying at the edge of a Benioff zone, indicating volcanic activity where the oceanic lithosphere is descending into the earth's interior

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island arc Scientific  

1. A usually curved chain of volcanic islands bounded on the convex side by a deep oceanic trench. Island arcs form in the overriding tectonic plates of subduction zones as the result of rising melt from the downgoing plate. The arcs are curved because of the curvature of the Earth. The Aleutian Islands, in Alaska, are an island arc. An island arc is a kind of volcanic arc.

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Etymology

Origin of island arc

First recorded in 1905–10

Example Sentences

Situated in the northeast of the Caribbean island arc, Anguilla lies perfectly within the North Atlantic hurricane belt.

From BBC • Aug. 31, 2025

The mountains are believed to have formed when an island arc in the Pacific Ocean collided with the New Guinea mainland about 10 million years ago.

From Science Daily • Nov. 9, 2023

Subduction of an oceanic plate beneath another oceanic plate, forming a trench and an island arc.

From Textbooks • Jan. 1, 2017

Dr. van Hinsbergen does not find the island arc hypothesis compelling, and Dr. Aitchison is equally unconvinced by the suggestion of India breaking in two before colliding with Asia.

From New York Times • May 18, 2015

We’re in another island arc, where volcanoes erupted and islands with their reefs formed, although this islands’s quite a lot older than the one we just visited.

From Scientific American • Mar. 7, 2012