coinsurance

[ koh-in-shoo r-uh ns, -shur- ]
/ ˌkoʊ ɪnˈʃʊər əns, -ˈʃɜr- /

noun

insurance underwritten jointly with another or others.
a form of property insurance in which an insurer assumes liability only for that proportion of a loss which the amount of insurance bears to a specified percentage of the value of the property.
  1. a form of health insurance in which the insured party contributes a specified percentage of the total cost of medical expenses after a deductible has been reached.
  2. the percentage contributed by the insured party: My coinsurance is 20%.Compare copay.

Origin of coinsurance

First recorded in 1885–90; co- + insurance

British Dictionary definitions for coinsurance

coinsurance
/ (ˌkəʊɪnˈʃʊərəns, -ˈʃɔː-) /

noun

a method of insurance by which property is insured for a certain percentage of its value by a commercial insurance policy while the owner assumes liability for the remainder
joint insurance held by two or more persons