/ Dictionary / Index C Clayton Antitrust Act: Meaning and Definition of Find definitions for: Clay'ton Antitrust' Act" Pronunciation: [key] an act of Congress in 1914 supplementing the Sherman Antitrust Act and establishing the FTC. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Clayton Clayton-Bulwer Treaty Related Content Daily Word Quiz: garrulous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language