(n.) The period of a synodic revolution of the moon, or the time from one new moon to the next; varying in length, at different times, from about 29/ to 29/ days, the average length being 29 d., 12h., 44m., 2.9s.

abundant year academic year bissextile year calendar month calendar year century common year day decade decennary decennium defective year fiscal year fortnight hour leap year lunar month lunar year lunation luster lustrum man-hour microsecond millennium millisecond minute moment month moon quarter quinquennium regular year second semester session sidereal year solar year sun term trimester twelvemonth week weekday year