religious festival

A religious festival is a time of special importance marked by adherents to that religion. Religious festivals are commonly celebrated on reoccurring cycles in a calendar year or lunar calendar. This means that, because ancient calendars were not very accurate, the exact date of the festival changes each year.
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Noun
1. a festival having religious significance
(synonym) church festival
(hypernym) festival
(hyponym) octave
(part-meronym) feast day, fete day