A lineal descendant, in legal usage, refers to a blood relative in the direct line of descent. The children, grandchildren, great-grandchildren, etc. of a person.
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 Native American tribes in the United States, tribal enrollment can be determined by lineal descent, as opposed to a minimum blood quantum.[1] Lineal descent means that anyone directly descended from original tribal enrollees could be eligible for tribal enrollment, regardless of how much Indian blood they have.