出典:Wiktionary
French épacte, from Ancient Greek ἐπακταί (epaktaí, “intercalary days”), feminine plural of ἐπακτός (epaktós, “brought on または in, added”).
epact (複数形 epacts)
出典:Wikipedia
出典:『Wikipedia』 (2011/06/04 20:57 UTC 版)
The epact (Latin epactae, from Greek: epaktai hèmerai = added days) was originally defined as the age of the moon in days on January 1, and occurs primarily in connection with tabular methods for determining the date of Easter. It varies (usually by 11 days) from year to year, because of the difference between the solar year of 365 days and the lunar year of 354 days.