Decreasing term life insurance is a policy where the benefit declines on either a monthly or annual basis. The size of the policy continues decreasing until either the policy pays out or until the end of the coverage period.
A decreasing term life insurance policy typically works best to cover a loan or other financial obligation that will reduce in size over a known period of time. For example, if you want just enough life insurance to cover your mortgage so that your family would be able to keep your home after you pass away.