October is the tenth month of the year in the Gregorian calendar, and it gets its name from the Latin word "octo," which means "eight."
The Roman calendar, from which the Gregorian calendar is derived, originally had only ten months. March was the first month, and December was the tenth. October was the eighth month in this early Roman calendar, hence its name.
When the Roman calendar was reformed by Julius Caesar, two new months, January and February, were added to the beginning of the year. This made October the tenth month, but the name remained unchanged.
Therefore, although October is now the tenth month, it retains its name from its original position as the eighth month in the ancient Roman calendar.