Metonic cycle

Me·​ton·​ic cycle | \ meˈtänik- \

Definition of Metonic cycle

: a period of 19 years after the lapse of which the phases of the moon return to a particular date in the calendar year:
a : one of the 19-year periods reckoning from June 27, 432 b.c., that were used in determining lengths of years and the placing of the intercalary month in the ancient Greek calendar
b : one of the 19-year periods reckoning from 1 b.c. that are used in determining the date of Easter in the Gregorian calendar

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

History and Etymology for Metonic cycle

Meton, 5th century b.c. Greek astronomer + English -ic

Keep scrolling for more

Learn More about Metonic cycle

Statistics for Metonic cycle

Cite this Entry

“Metonic cycle.” Dictionary, Merriam-Webster, Accessed 11 Aug. 2020.

Comments on Metonic cycle

What made you want to look up Metonic cycle? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Original Meanings Quiz

  • rembrandt painting a young scholar and his tutor
  • Which of the following is the earliest known sense of the word awe?
Spell It

Can you spell these 10 commonly misspelled words?

Syn City

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!