- lineal, direct - in a straight unbroken line of descent from parent to child; "lineal ancestors"; "lineal heirs"; "a direct descendant of the king"; "direct heredity"
Antonyms: collateral, indirect
- lineal - arranged in a line
Antonyms: planar, two-dimensional (indirect, via cubic, linear)
Antonyms: cubic, three-dimensional (indirect, via linear, planar)