/ Dictionary / Index C cost-share: Meaning and Definition of Find definitions for: cost-share Pronunciation: (kôst'shâr", kost'-), [key] — -shared, -shar•ing. to share the cost of: to cost-share a joint venture. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. costrel cost sheet Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language