/ Dictionary / Index C coinsure: Meaning and Definition of Find definitions for: co•in•sure Pronunciation: (kō"in-shoor', -shûr'-), [key] — -sured, -sur•ing. to insure jointly with another or others. to insure on the basis of coinsurance. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: coinsure (Thesaurus) coinsurance coinsurer Related Content Daily Word Quiz: knead Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language