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noun, vol·ca·no \väl-ˈkā-(ˌ)nō, vȯl-\

Simple Definition of volcano

  • : a mountain with a hole in the top or side that sometimes sends out rocks, ash, lava, etc., in a sudden explosion (called an eruption)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of volcano

plural volcanoes or volcanos

  1. 1 :  a vent in the crust of the earth or another planet or a moon from which usually molten or hot rock and steam issue; also :  a hill or mountain composed wholly or in part of the ejected material

  2. 2 :  something of explosively violent potential

Examples of volcano in a sentence

  1. The volcano last erupted 25 years ago.

  2. <beset by prolonged heat and lingering racial tension, the city was like a seething volcano>

Illustration of volcano

Origin of volcano

Italian or Spanish; Italian vulcano, from Spanish volcán, ultimately from Latin Volcanus Vulcan

First Known Use: 1613

VOLCANO Defined for Kids


noun vol·ca·no \väl-ˈkā-nō, vȯl-\

Definition of volcano for Students

plural volcanoes or volcanos

  1. 1 :  an opening in the earth's crust from which hot or melted rock and steam erupt

  2. 2 :  a hill or mountain composed of material thrown out in a volcanic eruption

History for volcano

Before Columbus, Europeans knew only the handful of active volcanoes long familiar to sailors in the Mediterranean, such as Vesuvius in Italy. There was no general word to describe a mountain that emitted fire. This situation changed in the 1500s, however, when the Spanish conquistadors came upon the great volcanic peaks of Mexico, Central America, and the Andes. In the writings of the conquistadors the word used for these mountains was volcán, whose roots lie in the ancient world. Vulcanus, the Roman god of fire, was particularly associated with the volcanic Lipari Islands off the coast of Sicily—one of which is still called Vulcano in Italian. Through Arabic, Latin Vulcanus was brought to Spanish as a name for fiery peaks, and from Spanish to Italian, French, and English.

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