volcano

American  

[vol-key-noh] / vɒlˈkeɪ noʊ /

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.

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volcano British  

/ 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

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volcano Scientific  

/ vŏl-kā′nō /

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

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volcano Cultural  

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

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Discover More

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.)

Etymology

Origin of volcano

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

Explanation

When the earth's crust cracks open and spews hot lava and gases, you've got a volcano on your hands. You better run. The noun volcano comes from the name of the Roman god of fire, Vulcan. The Romans believed Vulcan had a forge in Mt. Etna, a volcano in Italy. The term can be applied to a vent in a planet's surface or crust. Lava, ash, and gas escape through the vent. The term volcano can also apply to a mountain created by such a vent.

Example Sentences

Satellite data revealed that the ground above the volcano rose by about 6 centimeters, confirming that magma had entered the shallow crust beneath the island.

From Science Daily • May 14, 2026

In January 2022, the underwater volcano Hunga Tonga-Hunga Ha'apai in the South Pacific produced one of the most powerful eruptions in modern history.

From Science Daily • May 10, 2026

More than a year earlier, he had completed his second arduous journey to the foothills of the inactive volcano of Chimborazo, in Ecuador, to make preparatory drawings and oil sketches for this roughly 10-foot-wide work.

From The Wall Street Journal • May 1, 2026

And while it might look like a mini volcano, it’s far from it.

From Los Angeles Times • Apr. 24, 2026

“In those days, weeks, months, years, now decades since 1980, Mount St. Helens has become the master teacher—an ideal lab for volcano studies,” said Carolyn Driedger.

From "Mountain of Fire" by Rebecca E. F. Barone

Related Words

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