Lineal

Descending in a direct line from an ancestor; hereditary; derived from ancestors; -- opposed to collateral; as, a lineal descent or a lineal descendant.

Inheriting by direct descent; having the right by direct descent to succeed (to).

Composed of lines; delineated; as, lineal designs.

In the direction of a line; of or pertaining to a line; measured on, or ascertained by, a line; linear; as, lineal magnitude.