/ Dictionary / Index P PSE: Meaning and Definition of Find definitions for: PSE. Pronunciation: [key] See Pidgin Sign English. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. PSD psec 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