lunar calendar

a calendar based on lunar cycles

• Roman calendar — the lunar calender in use in ancient Rome; replaced by the Julian calendar in 46 BC
• Muhammadan calendar, Mohammedan calendar, Moslem calendar, Muslim calendar — the lunar calendar used by Moslems; dates from 622 AD (the year of the Hegira); the beginning of the Moslem year retrogresses through the solar year completing the cycle every 32 years

• calendar — a system of timekeeping that defines the beginning and length and divisions of the year