co ‧ in ‧ sur ‧ ance /ˌkəʊɪnˈʃʊərəns $ ˌkoʊɪnˈʃʊr-/ BrE AmE noun [uncountable] American English
1 . a type of insurance in which the payment is split between two people, especially between an employer and a worker:
health coinsurance
2 . insurance that will only pay for part of the value or cost of something