Metonic cycle

Metonic cycle

[mi-ton-ik]
noun Astronomy.
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.

Origin:
1880–85; named after Meton, 5th-century b.c. Athenian astronomer; see -ic

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To Metonic cycle
Collins
World English Dictionary
Metonic cycle (mɪˈtɒnɪk)
 
n
See also golden number a cycle of nearly 235 synodic months after which the phases of the moon recur on the same days of the year
 
[C17: named after Meton, 5th-century bc Athenian astronomer]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Encyclopedia Britannica
Encyclopedia

metonic cycle

in chronology, a period of 19 years in which there are 235 lunations, or synodic months, after which the Moon's phases recur on the same days of the solar year, or year of the seasons. The cycle was discovered by Meton (fl. 432 BC), an Athenian astronomer. Computation from modern data shows that 235 lunations are 6,939 days, 16.5 hours; and 19 solar years, 6,939 days, 14.5 hours. See also golden number.

Learn more about Metonic cycle with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature
FAVORITES
RECENT

;