/ Dictionary / Index M mountain wave: Meaning and Definition of Find definitions for: moun'tain wave" Pronunciation: [key] the wavelike effect, characterized by severe updrafts and downdrafts, that occurs when rapidly flowing air encounters the steep front of a mountain range. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mountain viscacha mountain whitefish 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