/ Dictionary / Index M Mission Viejo: Meaning and Definition of Find definitions for: Mis'sion Vi•e'jo Pronunciation: (vē-ā'hō), [key] a city in SW California. 50,666. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mission specialist missis 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