a cycle of nearly 235 synodic months after which the phases of the moon recur on the same days of the year
See also golden number
Word origin
C17: named after Meton, 5th-century bc Athenian astronomer
Metonic cycle in American English
(məˈtɑnɪk)
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 finding the date of Easter