noun
seventh-generation descendant; great-great-great-great-great-grandchild
A highly specific genealogical term referring to a descendant seven generations removed. Extremely rare in everyday language; mostly encountered in historical or family record contexts.
系図によると、彼はあの武将の仍孫にあたるらしい。
According to the family tree, he seems to be the seventh-generation descendant of that warlord.