/ Dictionary / Index V volcaniclastic: Meaning and Definition of Find definitions for: vol•can•i•clas•tic Pronunciation: (vol-kan"i-klas'tik), [key] — adj. Geol. pyroclastic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. volcanic glass volcanic neck Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language