/ Dictionary / Index D diaper rash: Meaning and Definition of Find definitions for: dia'per rash" Pronunciation: [key] a reddish inflammation of the buttocks occurring in infants usually as a result of irritation by ammonia formed as a breakdown product of urine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. diaper diaphaneity Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language