/ Dictionary / Index P pestilential: Meaning and Definition of Find definitions for: pes•ti•len•tial Pronunciation: (pes"tl-en'shul), [key] — adj. producing or tending to produce pestilence. pertaining to or of the nature of pestilence, esp. bubonic plague. pernicious; harmful. annoyingly troublesome. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pestilential (Thesaurus) pestilent pestle Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language