/ Dictionary / Index M mattrass: Meaning and Definition of Find definitions for: mat•trass Pronunciation: (ma'trus), [key] — n. Chem. matrass. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Mattoon mattress Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language