/ Dictionary / Index M Monaghan: Meaning and Definition of Find definitions for: Mon•a•ghan Pronunciation: (mon'u-gun, -han"), [key] — n. a county in the NE Republic of Ireland. 51,174; 498 sq. mi. (1290 sq. km). Co. seat: Monaghan. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. monadnock Mona Lisa* Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language