/ Dictionary / Index M mettlesome: Meaning and Definition of Find definitions for: met•tle•some Pronunciation: (met'l-sum), [key] — adj. spirited; courageous. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mettlesome (Thesaurus) mettle Metuchen Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language