A calendar that is based on the phases of the moon.
The most widely used calendar in the world, adopted in 1582 to correct errors in the Julian calendar.
A calendar introduced by Julius Caesar in 45 BCE, which was later corrected by Pope Gregory XIII in the Gregorian Calendar.
A year with an extra day, February 29, was added to the calendar to account for the discrepancy between the solar and lunar calendars.
A unit of time, typically based on the cycles of the moon, used to organize a calendar.
A unit of time consisting of seven days, used to organize a calendar.