30 April 2014
Such quaint terms! We seldom see them, when doing American research in relatively modern times; but when our research pushes back into Europe or the British Isles, in the eighteenth-century and earlier, we'll find these words peppering many sources. Here's a two-second tutorial:
Uterine Lineage: A female line across generations, with no intervening males. Historically, it has also been called "matrilineage." Genetically, it is known as the mitachondrial DNA line.
Agnatic Lineage: A male line across generations, with no intervening females. Historically, it is also known as the "patrilineage." Genetically, it is known as the Y-line.