/ Dictionary / Index M mud volcano: Meaning and Definition of Find definitions for: mud' volca'no Pronunciation: [key] a vent in the earth's surface through which escaping gas and vapor issue, causing mud to boil and occasionally to overflow, forming a conical mound around the vent. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mud turtle mud wasp Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language