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coinsurer

American  
[koh-in-shoor-er, -shur-] / ˌkoʊ ɪnˈʃʊər ər, -ˈʃɜr- /

noun

  1. a person or firm that contracts as an insurer jointly with another or others.

  2. an insured who is liable to bear part of the loss under a coinsurance provision.


Etymology

Origin of coinsurer

co- + insurer