euphrŏne — Lewis & Short
euphrŏne, es, f., = eu)fro/nh (the propitious), euphemism for
I night:
ut euethen Graeci dicimus stultum, et noctem euphronen, et furias Eumenidas,Amm. 22, 8, 33; cf. Lidd. and Scott, s. v. eu)fro/nh.