Caldera

n. basin-like crater at the summit of a volcano

n. American corporation headquartered in Utah, manufacturer of the OpenLinux operating system and other Linux-based business software products

A caldera is a volcanic feature formed by the collapse of land following a volcanic eruption. They are often confused with volcanic craters. The word 'caldera' comes from the Spanish language, meaning "cauldron".
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Noun
1. a large crater caused by the violent explosion of a volcano that collapses into a depression
(hypernym) volcanic crater, crater

n. caldera, basin-like crater at the summit of a volcano

n. boiler, copper; cauldron, large pot used for cooking or boiling liquids