Collateral kinsmen

COLLATERAL KINSMEN, descent, distribution. Those who descend from one and the same common ancestor, but not from one another; thus brothers and sisters are collateral to each other; the uncle and the nephew are collateral kinmen, and cousins are the same. The term collateral is used in opposition to the phrase lineal kinsmen. (q.v.)

A Law Dictionary, Adapted to the Constitution and Laws of the United States. By John Bouvier. Published 1856.