Insurance
Roles: policyholder, insurer, premium, claim, coverage, deductible, risk-pool, underwriting, moral-hazard
The contractual transfer of risk from a policyholder to an insurer in exchange for regular premium payments. Insurance operates by pooling many individual risks into a collective that is statistically predictable even when individual outcomes are not. As a source domain, insurance provides metaphors for any arrangement where a certain small cost is exchanged for protection against an uncertain large loss — hedging strategies, safety margins, redundant systems, and precautionary policies.