† out-grandfatherv.Obsolete (transitive) to do out of a grandfather.Apparently an isolated use.
ΘΚΠ
society > society and the community > kinship or relationship > kinsman or relation > grandparent > be a grandparent [verb (transitive)] > deprive of a grandfather
out-grandfather1747
1747 S. RichardsonClarissa I. xiii. 78 This little Syren is in a fair way to out-uncle, as well as out-grandfather us both!