/ Dictionary / Index R relative impediment: Meaning and Definition of Find definitions for: rel'ative imped'iment Pronunciation: [key] — Law. Law. a fact or circumstance that disqualifies from lawful marriage persons who are closely related. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. relative humidity relative index of refraction Related Content Daily Word Quiz: kiln Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language