неисповедимый

From LSJ

ὑπὲρ κεφαλῆς γῆρας ὑπερκρέμαται → old age hangs over one's head

Source

Russian > Greek

ἄβυσσος, ἀνεξιχνίαστος, ἀτέκμαρτος, ἀπέρατος