noun
great-great-great-grandchild; fifth-generation descendant
A precise kinship term for a descendant five generations down (child → grandchild → great-grandchild → great-great-grandchild → great-great-great-grandchild). Rare in everyday conversation; mainly encountered in genealogy, historical contexts, or formal family records.
家系図を調べると、来孫の代まで記録されていた。
When I examined the family tree, it was recorded down to the fifth-generation descendants.