/ Dictionary / Index V vulcanism: Meaning and Definition of Find definitions for: vul•can•ism Pronunciation: (vul'ku-niz"um), [key] — n. Geol. volcanism. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Vulcanian vulcanite Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language