How are the terms assurer, insured and assured used in insurance?

Accdg to Black’s Law, Insurer is synonymous with the term “assurer” or “underwriter”.

The terms “insured” and “assured” are generally used interchangeably; but strictly speaking, the term “insured” refers to the owner of the property insured or the person whose life is the subject of the contract of  insurance, while “assured” refers to the person for whose benefit the insurance is granted.

For ex:  A wife insures the life of her husband for her own benefit.  The wife is the assured, and the husband the insured.  The wife is the owner of the policy but she is not the insured.

In property insurance, like fire insurance, the insure is also the assured where the proceeds are payable to him.

Assured is also used sometimes as a synonym of “beneficiary.”  The beneficiary is the person designated by the terms of the policy as the one to receive the proceeds of the insurance.  He is the third party in a contract of life insurance, whose benefit the policy is issued and to whom the loss is payable.