Life Insurance (US Department of Veterans Affairs)

An operational definition of insurance is that it is
the benefit provided by a particular kind of indemnity contract, called an insurance policy;
that is issued by one of several kinds of legal entities (stock company, mutual company, reciprocal, or Lloyd's syndicate, for example), any of which may be called an insurer;
in which the insurer promises to pay on behalf of or to indemnify another party, called a policyholder or insured;
that protects the insured against loss caused by those perils subject to the indemnity in exchange for consideration known as an insurance premium.
http://lifefinanceinsurance.com