/ Dictionary / Index D dead set: Meaning and Definition of Find definitions for: dead set Pronunciation: (ded' set' for 1 2 ded' set&sec for 3), [key] firmly decided or determined; resolved: His family was dead set against the marriage. a serious or determined attempt; firm effort: He made a dead set at winning the championship. the stiff posture assumed by a hunting dog in indicating the presence and location of game. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Dead Sea Scrolls dead slow Related Content Daily Word Quiz: digression Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language