/ Dictionary / Index E eruption: Meaning and Definition of Find definitions for: e•rup•tion Pronunciation: (i-rup'shun), [key] — n. an issuing forth suddenly and violently; outburst; outbreak. the ejection of molten rock, steam, etc., as from a volcano or geyser. something that is erupted or ejected, as molten rock, volcanic ash, or steam. the breaking out of a rash or the like. a rash or exanthem. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: eruption (Thesaurus) erupt eruptive Related Content Daily Word Quiz: cetacean Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language