Final answer:
A Financial institution credit rating is a type of issuer credit rating primarily made on financial institutions and insurance companies.
Step-by-step explanation:
The type of issuer credit rating that is primarily made on financial institutions and insurance companies is called a Financial institution credit rating. Issuer credit ratings are assigned by agencies like Standard & Poor's and Moody's to assess the creditworthiness of entities seeking to borrow money through the issuance of securities.