προμηνύτρια
From LSJ
ἄλογον δὴ τὸ μήτε μάχης ἄρξασθαι μήτε τοὺς φίλους φυλάξαι, ἐὰν ὑπό γε τῶν βαρβάρων ἀδικῆσθε → It is irrational neither to begin battle nor to guard the friends, if you are ever wronged by the foreigners
English (LSJ)
ἡ,
A she who indicates before, Sch.rec. A.Th.402.
German (Pape)
[Seite 734] ἡ, die Anzeigerinn, Verrätherinn, Schol. Aesch. Spt. 387.