/ Dictionary / Index R respiratory quotient: Meaning and Definition of Find definitions for: res'piratory quo"tient Pronunciation: [key] — Physiol. Physiol. the ratio of the amount of carbon dioxide released by the lungs to the amount of oxygen taken in during a given period. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. respiratory distress syndrome respiratory system Related Content Daily Word Quiz: censure Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language