/ Dictionary / Index M mk.: Meaning and Definition of Find definitions for: mk. Pronunciation: [key] — pl. mks. mark (def. 1). markka. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Mjolnir MKS Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language