曾外祖母

great-grandmother (mother's grandmother)

surname Zeng

once / already / ever (in the past) / former / previously / (past tense marker used before verb or clause)

great- (grandfather, grandchild etc)

outside / in addition / foreign / external

surname Zu

ancestor / forefather / grandparents

mother's mother / maternal grandmother

father's mother / paternal grandmother

mother / elderly female relative / origin / source / (of animals) female