A Dictionary of Greek and Roman biography and mythology

(Μᾶ) signifies probably mother, as in Aeschylus (μᾶ γᾶ, Suppl. 890), who applies it to the earth to designate her as the mother of all. But, according to Stephanus Byzantinus (s. v. Μάσταυρα), Ma was the name of a nymph in the suite of Rhea, to whom Zeus entrusted the bringing up of the infant Dionysus. The same author tells us that Rhea herself was by the Lydians called Ma, and that bulls were sacrificed to her, whence the name of the town Mastaura was derived. (Comp. Welcker, Trilog. p. 167.)

[L.S]