ἄθεον

From LSJ

ἀθρόαις πέντε δραπὼν νύκτεσσιν ἔν θ' ἁμέραις ἱερὸν εὐζοίας ἄωτον → for five whole nights and days, culling the sacred excellence of joyous living | reaping the sacred bloom of good living for five full nights and as many days

Source

Russian (Dvoretsky)

ἄθεον: τό безбожие Plat., Plut.