The phrase “what number is September” refers to the ordinal number of September within the 12-month Gregorian calendar. For instance, September is the ninth month of the year, following August and preceding October.
Knowing the ordinal number of September is relevant in various contexts, such as scheduling, historical referencing, and educational purposes. It allows for a clear and concise understanding of a month’s position within the calendar year. A notable historical development in this regard is the adoption of the Gregorian calendar in 1582, which standardized the month numbering system used today.