ἀπορρᾳθυμέω
From LSJ
εἰ ἀποκρυπτόντων τῶν Μήδων τὸν ἥλιον ὑπὸ σκιῇ ἔσοιτο πρὸς αὐτοὺς ἡ μάχη καὶ οὐκ ἐν ἡλίῳ → if the Medes hid the sun, the battle would be to them in the shade and not in the sun
English (LSJ)
A leave off in faintheartedness or laziness, τινός X. Mem.3.7.9: abs., Pl.R.449c, D.8.75. Adv. ἀπορρᾱθῡμ-ήτως, v.l. for ἀποραμυθήτως, Jul.Or.8.252a.