What is a festival of the Roman Catholic and other churches in commemoration of the descent of the Holy Spirit on the apostles; which occurred on the day of Pentecost; -- called also Whitsunday. Shak called?

pentecost — A festival of the Roman Catholic and other churches in commemoration of the descent of the Holy Spirit on the apostles; which occurred on the day of Pentecost; -- called also Whitsunday. Shak. (Webster's 1913.)

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