γραΐδιον
From LSJ
κεραυνὸν ἐν γλώττῃ φέρειν → carry a thunderbolt on his tongue
English (LSJ)
τό, Dim. of γραΐς,
A old hag, Ar.Pl.536:—elsewh. contr. γρᾴδιον, ib.674, Philyll.5, X.An.6.3.22, D.18.260, Men.Georg.54, etc.: barbarous form γρᾴδιο Ar.Th.1194.
German (Pape)
[Seite 503] τό, dim. von γραῦς, altes Mütterchen, Ar. Plut. 536; Xen. An. 6, 1, 22; γρᾴδιον Dem. 18, 260 Philyll. Ath. XI, 485 b; vgl. Phryn. 88.