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