/ Dictionary / Index M mustachio: Meaning and Definition of Find definitions for: mus•ta•chio Pronunciation: (mu-stä'shō, -shē-ō", -stash'ō, -stash'ē-ō"), [key] — pl. -chios. a mustache. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mustachio (Thesaurus) mustache cup Mustafa Kemal Related Content Daily Word Quiz: censure Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language