Lineal

a.
  1. Descending in a direct line from an ancestor; hereditary; derived from ancestors; -- opposed to collateral; as, a lineal descent or a lineal descendant.
  2. Inheriting by direct descent; having the right by direct descent to succeed (to).
  3. Composed of lines; delineated; as, lineal designs.
  4. In the direction of a line; of or pertaining to a line; measured on, or ascertained by, a line; linear; as, lineal magnitude.
    5. Lineal measure ,
    the measure of length; -- usually written linear measure.