Insurance policies can be filled with words and phrases that are not commonly used in everyday conversation. Here are some of the most common insurance terms that you need to know. Coinsurance: The percentage (%) of your bill that the insurance will cover (after you pay the deductible) Deductible: The dollar amount of covered expenses you are responsible to pay the physician or hospital before the policy will pay any benefits. Copay: A set fee you pay for medical services, typically at the time