/ Dictionary / Index P PCV valve: Meaning and Definition of Find definitions for: PCV valve Pronunciation: [key] — Auto. Auto. a valve used to control and direct the flow of gases during positive crankcase ventilation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. PCV Pd Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language