/ Dictionary / Index S Securities and Exchange Commission: Meaning and Definition of Find definitions for: Secu'rities and Exchange' Commis"sion. Pronunciation: [key] See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. securement Securities Exchange Act Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language