/ Dictionary / Index P P wave: Meaning and Definition of Find definitions for: P wave Pronunciation: [key] a longitudinal earthquake wave that travels through the interior of the earth and is usually the first conspicuous wave to be recorded by a seismograph. Also calledCf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. PWA PWC 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