μητρομήτωρ
From LSJ
Ὅσον ζῇς, φαίνου, μηδὲν ὅλως σὺ λυποῦ· πρὸς ὀλίγον ἐστὶ τὸ ζῆν, τὸ τέλος ὁ χρόνος ἀπαιτεῖ. → While you live, shine; have no grief at all; life exists only for a short while, and time demands its toll.
English (LSJ)
Dor. ματρομάτωρ, ορος, ἡ,
A mother's mother, grandmother, Pi.O.6.84, Ael.NA11.16.