volcano

[vol-key-noh]

noun

plural

volcanoes, volcanos 

1. a vent in the earth's crust through which lava, steam, ashes, etc., are expelled, either continuously or at irregular intervals.

2. a mountain or hill, usually having a cuplike crater at the summit, formed around such a vent from the ash and lava expelled through it.

volcano

/ vɒlˈkeɪnəʊ /

noun

1. an opening in the earth's crust from which molten lava, rock fragments, ashes, dust, and gases are ejected from below the earth's surface

2. a mountain formed from volcanic material ejected from a vent in a central crater

volcano

1. An opening in the Earth's crust from which lava, ash, and hot gases flow or are ejected during an eruption.

2. A usually cone-shaped mountain formed by the materials issuing from such an opening. Volcanoes are usually associated with plate boundaries but can also occur within the interior areas of a tectonic plate. Their shape is directly related to the type of magma that flows from them—the more viscous the magma, the steeper the sides of the volcano.

3. ◆ A volcano composed of gently sloping sheets of basaltic lava from successive volcanic eruptions is called a shield volcano. The lava flows associated with shield volcanos, such as Mauna Loa, on Hawaii, are very fluid.

4. ◆ A volcano composed of steep, alternating layers of lava and pyroclastic materials, including ash, is called a stratovolcano. Stratovolcanos are associated with relatively viscous lava and with explosive eruptions. They are the most common form of large continental volcanos. Mount Vesuvius, Mount Fuji, and Mount St. Helens are stratovolcanos.

5. Also called composite volcano

6. See more at hot spot island arc tectonic boundary volcanic arc

volcano

1. A cone-shaped mountain or hill created by molten material that rises from the interior of the Earth to the surface.

Volcanoes tend to occur along the edges of tectonic plates.

Eruptions and lava flows associated with them can be very destructive. (See Mount Saint Helens and Mount Vesuvius.)

Word History and Origins

Origin of volcano¹

1605–15; < Italian < Latin Volcānus, variant of Vulcānus Vulcan

Word History and Origins

Origin of volcano¹

C17: from Italian, from Latin Volcānus _Vulcan ¹ , whose forges were believed to be responsible for volcanic rumblings

Example Sentences

Some volcanoes, including Mount St. Helens in Washington state and Quizapu in Chile, have occasionally released slow, gentle lava flows even when their magma was rich in gas and considered highly explosive.

Read more on Science Daily

Watkins, a geochemist who specializes in the behavior of minerals at high temperature and pressure, used laboratory equipment capable of simulating the conditions found deep in the crust or beneath a volcano.

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I feel like I’m doing a stair workout for gym class—if I was thrown into a volcano the period before.

Read more on Literature

A volcano in southern Japan erupted early Sunday sending a plume of ash and smoke into the sky and prompting a warning over ashfall.

Read more on Barron's

Rock from the subducting plates turns to magma when it reaches the mantle, creating hot spots that, over millennia, melt through the crust and break through as lava, forming volcanoes.

Read more on Literature

Related Words

• alp 
• bluff 
• butte 
• cliff 
• crag 
• elevation 
• eminence 
• height 
• mesa 
• mount 
• palisade 
• peak 
• pike 
• precipice 
• range 
• ridge 
• sierra 
• tor