eruption

n. act or instance of bursting forth suddenly; act or instance of breaking out (about a skin rash)

A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot, molten rock, ash and gases to escape from below the surface. Volcanic activity involving the extrusion of rock tends to form mountains or features like mountains over a period of time.Volcanoes are generally found where tectonic plates pull apart or come together. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by "divergent tectonic plates" pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by "convergent tectonic plates" coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust (called "non-hotspot intraplate volcanism"), such as in the African Rift Valley, the Wells Gray-Clearwater Volcanic Field and the Rio Grande Rift in North America and the European Rhine Graben with its Eifel volcanoes.
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Volcano is a disaster action film starring Tommy Lee Jones, Anne Heche, and Don Cheadle. It was directed by Mick Jackson, and was released in the United States on April 25, 1997, just months after the release of Dante's Peak, another film about a volcano with a similar plot. Geologists consider Volcano to be scientifically inaccurate compared to Dante's Peak.
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n. eruption, outbreak, outburst

(n.)
The breaking out of pimples, or an efflorescence, as in measles, scarlatina, etc.
  

(n.)
The act of breaking out or bursting forth; as: (a) A violent throwing out of flames, lava, etc., as from a volcano of a fissure in the earth's crust. (b) A sudden and overwhelming hostile movement of armed men from one country to another. Milton. (c) A violent commotion.
  

(n.)
That which bursts forth.
  

(n.)
A violent exclamation; ejaculation.
  

Noun
1. the sudden occurrence of a violent discharge of steam and volcanic material
(synonym) volcanic eruption
(hypernym) discharge
(hyponym) Plinian eruption
(derivation) erupt, belch, extravasate
2. symptom consisting of a breaking out and becoming visible
(hypernym) symptom
(hyponym) eczema vaccinatum, Kaposi's varicelliform eruption
3. (of volcanos) pouring out fumes or lava (or a deposit so formed)
(synonym) eructation, extravasation
(hypernym) action, activity, activeness
(derivation) erupt, belch, extravasate
(classification) vent, volcano
4. a sudden violent spontaneous occurrence (usually of some undesirable condition); "the outbreak of hostilities"
(synonym) outbreak, irruption
(hypernym) happening, occurrence, natural event
(hyponym) epidemic
(derivation) erupt, irrupt, flare up, flare, break open, burst out
5. a sudden very loud noise
(synonym) bang, clap, blast, loud noise
(hypernym) noise
(hyponym) water hammer
6. the emergence of a tooth as it breaks through the gum
(hypernym) emergence, egress, issue
(derivation) erupt, come out, break through, push through