Legal Definitions - second cousin

Definition: A second cousin is a relative who shares a great-grandparent with you. They are the child of your parent's cousin.

For example, if your father's cousin has a child, that child is your second cousin. You share a set of great-grandparents with them.

This means that you and your second cousin have a common ancestor, but you are not as closely related as first cousins. Second cousins share about 3.125% of their DNA.