holy day of obligation

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a day when Catholics must attend Mass and refrain from servile work, and Episcopalians must take Communion
• Hypernyms:
Christian holy day
• Hyponyms:
Solemnity of Mary, January 1, Ascension, Ascension Day, Ascension of the Lord,
Assumption, Assumption of Mary, August 15, All Saints' Day, Allhallows, November 1,
Hallowmas, Hallowmass, Immaculate Conception, December 8, Christmas, Christmas Day,
Xmas, Dec 25