noun
great-grandmother
Refers to one's own great-grandmother or someone else's great-grandmother. Commonly used in family contexts.
ひいおばあさんは今年で95歳になります。
My great-grandmother will be 95 years old this year.
ひいおばあさんから聞いた昔の話が面白い。
The old stories I heard from my great-grandmother are interesting.
Compound of ひい (prefix meaning 'great-' in family terms) + おばあさん (grandmother). The prefix ひい is of uncertain origin but is used to indicate an additional generation.