epact
/ˈiːpækt/noun
in sing.
- the number of days by which the solar year exceeds the lunar year闰余（阳历一年间超过阴历的日数）。
词源
mid 16th cent. (denoting the age of the moon in days at the beginning of the calendar year)： from French épacte, via late Latin from Greek epaktai （hēmerai） 'intercalated (days)', from epagein 'bring in', from epi 'in addition' + agein 'bring'.