Why is the ninth month called September?
late 14c., nowel "feast of Christmas," from Old French noel "the Christmas season," variant of nael, from Latin natalis (dies) "birth (day)," in Church Latin in reference to the birthday of Christ, from natus, past participle of nasci "be born" (Old Latin gnasci; see genus). The modern word in English, with the sense "a Christmas carol" (1811) probably is a separate borrowing from French. As a masc. proper name, from Old French, probably literally "of or born on Christmas."