/ Dictionary / Index D dead center: Meaning and Definition of Find definitions for: dead' cen'ter Pronunciation: [key] — Mach. Mach. Also called(in a reciprocating engine) either of two positions at which the crank cannot be turned by the connecting rod, occurring at each end of a stroke when the crank and connecting rod are in the same line. See under(def. 19a). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. deadbolt dead drop Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language