/ Dictionary / Index M martensite: Meaning and Definition of Find definitions for: mar•tens•ite Pronunciation: (mär'tn-zīt"), [key] — n. Metall. a metastable microconstituent of any of various forms of carbon steel, produced by undercooling sufficiently below the normal transformation temperature, esp. a hard, brittle product of the decomposition of austenite, produced in this way. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: martensite (Thesaurus) marten Martha Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language