September is the ninthmonth of the year in the Gregorian Calendar, with 30 days. The name comes from the Latin septem, for "seven" -- September was originally the seventh month of the year, before January and February were inserted.
In Greek civilization, September was called Boedromion.
In the Irish Calendar the month is called Meán Fómhair (literally "Middle of Autumn") and is the middle month of the Autumn season.