This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Belonging to or being in the direct line of descent from an ancestor.

adj. Derived from or relating to a particular line of descent; hereditary.

adj. Linear.

adj. Of a family relationship that includes mothers, fathers, sisters, brothers, daughters, and sons, etc. as opposed to collateral.

adj. Descending in a direct line from an ancestor; hereditary; derived from ancestors; -- opposed to collateral.

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

adj. Composed of lines; delineated.

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

Of or pertaining to a line or length; extending in a line; involving the single dimension of length: as, lineal measure; a lineal foot.

Proceeding in a direct or unbroken line; hereditary; unbroken in course: distinguished from collateral: as, lineal descent; lineal succession.

Pertaining or relating to direct descent; hereditary in quality or character; having an ancestral basis or right.

Allied by direct descent.

Of or pertaining to the line or officers of the line in the army or navy.

adj. arranged in a line

adj. in a straight unbroken line of descent from parent to child

"It has rarely happened that a crown has been transmitted from father to son, in lineal descent, for seventeen reigns."

linear    one-dimensional    unilateral    patrilinear    matrilineal    patrilineal    matrilinear   

collateral   

lineal measure   

linear    lineage    line   

matrilineal    patrilineal   

delineated    linear    direct    running   

matrilineal    patrilineal   

rightful    rightfull    apostolical    intestate    mixed-race    putative    ape-like    unmodified    fishlike    illegitimate