Metonic cycleMe·ton·ic cycle
a period of about 19 years (almost 235 lunar revolutions), in which the phases of the moon repeat on the same dates as in the previous period: used for determining the date of Easter
Origin of Metonic cycleafter Meton, Athenian astronomer (5th circa )
A period of 235 lunar months, or about 19 years in the Julian calendar, at the end of which the phases of the moon recur in the same order and on the same days as in the preceding cycle.
Origin of Metonic cycleAfter Meton, (fl. fifth century BC), Athenian astronomer.
(plural Metonic cycles)
- (astronomy, calendar studies) A particular approximate common multiple of the tropical year and the synodic month; in other words, the 19-year period over which the lunar phases occur on the same dates.
- According to the Metonic cycle, a lunar calendar begins on the same solar date every 19 years.