eruption

noun

1. an issuing forth suddenly and violently; outburst; outbreak.
2. Geology. the ejection of molten rock, steam, etc., as from a volcano or geyser.
3. something that is erupted or ejected, as molten rock, volcanic ash, or steam.
4. Pathology.
   1. the breaking out of a rash or the like.
   2. a rash or exanthem.

n.

early 15c., from Middle French éruption (14c.) and directly from Latin eruptionem (nominative eruptio) “a breaking out,” noun of action from past participle stem of erumpere “break out, burst forth,” from ex- “out” (see ex-) + rumpere “to break, rupture” (see rupture (n.)).

n.

1. An appearance of a rash or blemish on the skin.
2. Such a rash or blemish.
3. The emergence of a tooth through the gums.

1. The release of gas, ash, molten materials, or hot water into the atmosphere or onto the Earth’s surface from a volcano or other opening in the Earth’s surface.