Nychthemeron
（重定向自Nycthemeron）
Nychthemeron /nɪkˈθɛmərɒn/, occasionally nycthemeron or nuchthemeron (Greek νυχθήμερον from the words nykt- "night", and hemera "day, daytime"), is a period of 24 consecutive hours. It is sometimes used, especially in technical literature, to avoid the ambiguity inherent in the term day.