IPA: /ˈriːɪnˌʃʊrər/
KK: /ˈriːɪnˌʃʊrər/
A company or organization that provides insurance to other insurance companies, helping them manage risk by covering some of their potential losses.
The reinsurer helped the insurance company recover from the financial impact of the natural disaster.
Reinsurer → It is formed from "re-" (meaning again) and "insurer" (from the Latin "securare", meaning to make safe). The word "reinsurer" refers to a company that provides insurance to other insurance companies, effectively making them safe again against large losses.
Think of someone making an insurance company 'safe again' — 're-' means again, and 'insurer' relates to making safe.