νομοθέτης, today’s Greek word of the day, comes from Philo’s de mundi opificio (If I am not mistaken, the translation being “Concerning the Creation of the World”).
νομοθέτης is made up of two words: νόμος “law” and τίθημι “to give.” Μωυσῆς ῆν μεγάλος προφήτης καὶ νομοθέτης ἐν Ισραηλ “Moses was a great prophet and lawgiver in Israel.” [note: this is not a quote form Philo but a fabricated sentence]
A few statistics: νομοθέτης is used once in the NT (James 4:12), once in the LXX (Psalm 9:21), 130 times in Philo, 51 times in Josephus, once in the Apostolic Fathers (Barn 21:4) and 10 times in the Pseudepigrapha (mainly in Aristeas and Aristobulos).