κρύφα
From LSJ
Κύριε, σῶσον τὸν δοῦλον σου κτλ. → Lord, save your slave ... (mosaic inscription from 4th cent. church in the Negev)
English (LSJ)
[ῠ], Adv., (κρύπτω)
A = κρύβδα, without the knowledge of, c. gen., Th.1.101. 2 abs., secretly, Aen.Tact.2.4; by ballot, Th. 4.88; obscurely, κ. καὶ δι' αἰνιγμάτων Plu.2.1125e.