A dependent is a person who is eligible for coverage under a policyholder’s health insurance coverage. The policyholder is the individual who has primary eligibility for coverage – for example, an employee whose employer offers health insurance benefits. A dependent may be a spouse, domestic partner, or child. You can cover your biological, adopted, and step children. In some cases, you may also be able to cover a grandchild, an adult child with a disability, a foster child or someone for whom you are the legal guardian.