ἀΐδιον

From LSJ

κοινὴ γὰρ ἡ τύχη καὶ τὸ μέλλον ἀόρατον → fortune is common to all, the future is unknown | fortune is common to all and the future unknown | fate is common to all and the future unknown

Source

Russian (Dvoretsky)

ἀΐδιον: τό
1 вечность Plat.; ἐς ἀ. Thuc. на вечные времена; εἰς ἀ. συναρτῆσαι τὴν τῆς ἀποδείξεως ἀνάγκην Arst. сделать доказательство навеки незыблемым;
2 вечное (τὸ ἀθάνατον καὶ ἀ. Plat.).