proavia
From LSJ
Καλὸν φέρουσι καρπὸν οἱ σεμνοὶ τρόποι → Mores decori frugis est pulchrae seges → Ein ehrbarer Charakter bringt willkommne Frucht
Latin > English (Lewis & Short)
prŏ-ăvĭa: ae,
I f, a grandfather's or grandmother's mother, a great-grandmother (post-Aug.), Suet. Calig. 10; cf. Dig. 38, 10, 1; 10.