μητρομήτωρ
From LSJ
ἔστιν δέ που ἡ μὲν ἐπὶ σώμασι γυμναστική, ἡ δ' ἐπὶ ψυχῇ μουσική → I think I am right in saying that we have physical exercise for the body and the arts for the soul
English (LSJ)
Dor. ματρομάτωρ, ορος, ἡ,
A mother's mother, grandmother, Pi.O.6.84, Ael.NA11.16.
German (Pape)
[Seite 180] ορος, ἡ, Mutter der Mutter, Großmutter mütterlicher Seits; Ael. N. A. 11, 16; Pind. Ol. 6, 84, in dor. Form ματρομάτωρ.