νυχθ-ήμερος · nychth-ēmeros — LSJ
lasting a day and night, δρόμοι Peripl.M.Rubr. 15 ; πλοῦς Scymn. 957.
as Subst. νυχθ-ήμερον, τό, a night and a day, the space of 24 hours, 2 Ep.Cor. 11.25, Gal. 7.508, Cleom. 1.6, Ptol. Alm. 3.9, Herm. ap. Stob. 1.21.9, Gp. 5.8. S, etc.