nycthemeronyoudaoicibaDictYouDict[nycthemeron 词源字典]
"A period of twenty-four hours, consisting of a day and a night", Late 17th cent.; earliest use found in Henry More (1614–1687), philosopher, poet, and theologian. From Hellenistic Greek νυχθήμερον period of a day and a night, use as noun of neuter singular of νυχθήμερος lasting for a day and a night from ancient Greek νυκτ-, νύξ night + ἡμέρα day.[nycthemeron etymology, nycthemeron origin, 英语词源]