/ Dictionary / Index P P.SS.: Meaning and Definition of Find definitions for: P.SS. Pronunciation: [key] postscripts. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. PSRO psst Related Content Daily Word Quiz: designate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language