Lineal descendant

Adopted children, for whom adoption statutes create the same rights of heirship as children of the body, come within the meaning of the term "lineal descendants," as used in a statute providing for the non-lapse of a devise where the devisee predeceases the testator but leaves lineal descendants.

Among some Native American tribes in the United States, tribal enrollment can be determined by lineal descent, as opposed to a minimum blood quantum. Lineal descent means that anyone directly descended from original tribal enrollees could be eligible for tribal enrollment, regardless of how much native blood they have.

The antonym of descendant is antecedent.

Collateral descendant

A collateral descendant is a legal term for a relative descended from a sibling of an ancestor, and thus a niece, nephew, aunt, uncle, or cousin.