The nu ephelkustikon in Ancient Greek grammar refers to an optional word-final -n that appears in various contexts. Its origins are certainly of polygenetic nature. Examples are particles like ke(n), pronouns like egō(n) and desinences like Dative plural -si(n). Nu (upper case Ν, lower case ν) is the 13th letter of the Greek alphabet. ... Ancient Greek refers to the stage in the history of the Greek language corresponding to Classical Antiquity, which normally applies on two ancient periods of Greek history: Archaic and Classic Greece. ...