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Webster 1913 Edition
Whitsunday
Whit′sun-day
,Noun.
[
White
+ Sunday
.] 1.
(Eccl.)
The seventh Sunday, and the fiftieth day, after Easter; a festival of the church in commemoration of the descent of the Holy Spirit on the day of Pentecost; Pentecost; – so called, it is said, because, in the primitive church, those who had been newly baptized appeared at church between Easter and Pentecost in white garments.