lunar cycle

American  

[loo-ner sahy-kuhl] / ˈlu nər ˈsaɪ kəl /

noun

Astronomy.

1. a cycle of 235 synodic months, very nearly equal to 19 years, after which the new moon occurs on the same day of the year as at the beginning of the cycle with perhaps a shift of one day, depending on the number of leap years in the cycle.

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Etymology

Origin of lunar cycle

First recorded in 1695–1705

Example Sentences

We usually get 12 full Moons a year, but as this doesn't quite match up with the lunar cycle we get an additional one roughly every two and half years.

From BBC • Jan. 30, 2026

Native Americans constructed the earthworks, including eight long earthen walls, that correspond to lunar movements and align with points where the moon rises and sets over the 18.6-year lunar cycle.

From Seattle Times • May 27, 2024

Ramadan lasts one lunar cycle, measured from new moon to new moon.

From Los Angeles Times • Apr. 9, 2024

The new moon will mark the beginning of the next 29.5-day lunar cycle.

From Scientific American • Aug. 30, 2023

The lunar cycle contained 6939 days 18 hours, whereas the exact time of 235 lunations, as we have already seen, is 235 � 29.530588 = 6939 days 16 hours 31 minutes.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" by Various