Breadcrumb Home > Dictionary > Index M mCi: Meaning and Definition of Find definitions for: mCi Pronunciation: [key] millicurie; millicuries. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. MChin McIntire ✖ Related Content Daily Word Quiz: glissade Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language