November (Roman month) November (Roman month) November (from Latin "novem", "nine") or mensis November was originally the ninth of ten months on the Roman calendar, following October ("octo", "eight") and preceding December ("decem", "ten"). It had 29 days. In the reform that resulted in a 12-month year, November became the eleventh month, but retained its name, as did the other months from September through December. A day was added to November during the Julian calendar reform in the mid-40s BC. The outstanding event during November was the Plebeian Games from the 4th through the 17th. The month had few other festivals. It was
Lunar calendar to produce a lunisolar calendar. A 49-month cycle was proposed as the basis of an alternative Easter computation by Isaac Newton around 1700. The tabular Islamic calendar's 360-month cycle is equivalent to 24×15 months, minus a correction of one day. Lunar calendar A lunar calendar is a calendar based upon the monthly cycles of the Moon's phases (synodic months), in contrast to solar calendars, whose annual cycles are based only directly upon the solar year. The most commonly used calendar, the Gregorian calendar, is a solar calendar system that originally evolved out of a lunar calendar system. A purely lunar