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vol·ca·no

(vŏl-kānō)

n. pl. vol·ca·noes or vol·ca·nos

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

b. A similar opening on the surface of another celestial object.

2. A usually cone-shaped mountain formed from the materials issuing from such an opening.

[Italian, from Spanish volcán or Portuguese volcão, both probably from Latin volcānus, vulcānus, fire, flames, from Volcānus, Vulcan.]

(click for a larger image)

volcano

cutaway of an erupting volcano

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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