Metonic cycle

American  

[mi-ton-ik sahy-kuhl] / mɪˈtɒn ɪk ˈsaɪ kəl /

noun

Astronomy.

1. lunar cycle.

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Metonic cycle British  

/ mɪˈtɒnɪk /

noun

1. 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

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Etymology

Origin of Metonic cycle

First recorded in 1880–85; named after Meton, 5th-century b.c. Athenian astronomer; -ic

Example Sentences

This figure was a reference to the 19-year period relation of the moon known as the Metonic cycle, named after Greek astronomer Meton but discovered much earlier by the Babylonians.

From Scientific American

As regards the second point, the precise years of the intercalated months depend upon, and vary with, the year that we may select as the apparent first year of a set of 19 years, and it is not easy to arrange the Hindu years in sets answering to a direct continuation of the Metonic cycle.

From Project Gutenberg

The phases of the moon being thus brought into comparison with the rotation of the earth, a cycle was discovered by Meton, now known as the Metonic cycle, useful also in predicting eclipses, which comprised nineteen years, during which time 235 lunations will have very nearly occurred, and the full moons will return to the same dates.

From Project Gutenberg

This period being that of the metonic cycle of the moon, shows that if this could have really been discovered by them, they must have had a long acquaintance with astronomy.

From Project Gutenberg

Calippus, therefore, in order to make a correction of the Metonic cycle, proposed to quadruple the period of Meton, and deduct one day at the end of that time by changing one of the full months into a deficient month.

From Project Gutenberg