/ Dictionary / Index M metolazone: Meaning and Definition of Find definitions for: me•to•la•zone Pronunciation: (me-tō'lu-zōn"), [key] — n. Pharm. a thiazide diuretic, CHClNOS, used in the treatment of hypertension and as a diuretic in patients with chronic renal failure. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Metol Metonic cycle Related Content Daily Word Quiz: winsome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language