a fixed cost for a service paid by someone who has insurance (= an agreement that a company will pay certain costs for health care, etc.) each time they use that service. This system is used in the US, Germany, and some other countries.

Because she had health insurance, her only expense was a $10 copay. 因为她有医疗保险，所以只需支付10美元的共付费用。

A growing number of people don't have insurance or can't afford the copayments and deductibles their insurance policies require. 越来越多人没有保险，或者无力负担保险合同规定的共付费用和免赔额。