descendancy

noun3

1. •
   The quality or condition of being a descendant.

   • The principal concern of the priestly writers was to legitimate the role of Aaron by demonstrating his descendancy from the priestly lineage of Levi. — 1993
2. •
   Descendants considered collectively.

   • His sections in the book include Types of Genealogical Projects (pedigrees, lineages, descendancies, relationships). — 1989
3. •
   The opposite of ascendancy; the condition of being in the process of losing power or control.