Νεῖλος

Neilos: a city of Egypt. Hecataeus, in his Periegesis of it: “<***> and a sanctuary of Neilos the river.” The ethnic of the city is Neilopolites. But if the city is called simply Neilos, it ought to be accompanied by the possessive adjective from the river, Neilaios, as Apollonius says: “For as many possessive adjectives as, without iota, make either the genitive of the archetype or the nominative—these alone are pronounced with iota: Poseidōnios, Helikōnios, Rhōdios, Sakios. But those whose penult is by nature with a diphthong never produce the aforesaid formation; for neither kēpaios nor Neilaios admits an ethnic in accordance with it.”