a chain, often arc-shaped, of volcanic islands. These are undersea volcanoes which have grown through repeated eruptions to break the surface. They are the product of a subduction zone where either the continental plate is so low lying that its edge is submerged, or two pieces of oceanic plate have collided, the denser being subducted.
Geography Dictionary & Glossary for Students \\ ITS Tutorial School (ITS) - Hong Kong.