Why is October the tenth and not the eighth month?
There are eight notes in an octave and eight voices are needed to form an Octet. The word oct, octo or octa comes from an old Greek word for eight, and as the prefix to a word it indicates eight sides, parts or sections. October by rights should be the eighth month, and at one time it was. The early Roman calendar had 10 properly named months. Martius, now March, was the first, Quintilius was the fifth, sextilius was the sixth and October the Eighth month of the year. Julius Caesar streamlined this calendar to agree with the days of the real year. In his honor, Quintilius was renamed July and later Sextilius was named August for his nephew Augustus. January and February were added to make a 12 month calendar, but the old Roman months were not brought up to date with proper new names and numbers. Martius, named for the first, became the third month and October, named as the Eighth, became the tenth month of the modeled calendar.
