/ Dictionary / Index P pertussis: Meaning and Definition of Find definitions for: per•tus•sis Pronunciation: (pur-tus'is), [key] — n. Pathol. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pertussis (Thesaurus) perturbative Peru Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language