Gregorian calendar
Từ liên quan
yearmonthdayweekleap yeardatetimechronologyepocheracenturymillenniumdecadequartersemestersolsticeequinoxastronomyorbitrotationrevolutionsunearthmoontropical yearpapacyliturgyanniversaryscheduleagendaplanneralmanacchronometertimestampdurationintervalperiodcycleintercalationprecisionstandardizationreformsynchronizationtimezonemeridianlongitudelatitudehorizonzenithnadirastrolabesundialclockwatch